Kind: captions
Language: en
why weren't we pushing towards economic
fusion and new materials and new methods
of heat extraction and so forth because
everybody knew Fusion was 40 years away
and now it's four years away
the following is a conversation with
Dennis white nuclear physicist at MIT
and the director of the MIT plasma
science infusion center
this is the Lex Friedman podcast to
support it please check out our sponsors
in the description and now dear friends
here's Dennis White
let's start with a big question what is
nuclear fusion is the underlying process
that powers the universe so as the name
implies it fuses together or brings
together
two different elements technically
nuclei that come together and if you can
push them together close enough that you
can trigger essentially a reaction what
happens is that the the element
typically changes so this means that you
change from one element to another
chemical element to another underlying
what this means is that you change the
nuclear structure this rearrangement
through equals mc squared releases large
amounts of energy so Fusion is the
fusing together of lighter elements into
heavier elements and when you go through
it you say oh look so here are the
initial elements typically hydrogen and
they had a particular Mass rest Mass
which means just the mass when they're
with no kinetic energy and when you look
at the product afterwards it has less
rest mass and so you go well how is that
possible because you have to keep Mass
but mass and energy are the same thing
which which is what equals mc squared
means and the the conversion of this
comes into kinetic energy namely energy
that you can use in some way and that's
what happens in the center of stars so
Fusion is literally the reason life is
is viable in the universe so Fusion is
happening in our sun and what are the
elements the elements are hydrogen that
are coming together it goes through a
process which just probably gets a
little bit too detailed but there's it's
a somewhat complex catalyzed process
that happens in the center of stars but
in the end stars are Big Balls of
hydrogen which is the lightest it's the
simplest element the lightest element
the most abundant element most of the
universe is hydrogen and and it's
essentially a sequence through which
these processes occur that you end up
with helium
so those are the primary things and the
reason for this is because
helium has features as a nucleus like
the interior part of the atom that is
extremely stable and the reason for this
is helium has two protons and two
neutrons these are the things that make
up nuclei that make up all of us along
with electrons and because it has two
pairs it's extremely stable and for this
reason it when you convert the hydrogen
into helium it just wants to stay helium
and it wants to release kinetic energy
so stars are
basically conversion engines of hydrogen
into helium and I mean this also tells
you why you love Fusion I mean because
our sun will last you know 10 billion
years approximately that's along the
fuel will last but to do that kind of
conversion you have to have extremely
high temperatures it is one of the
criteria for doing this but it's the
easiest one to understand and why is
this it's because
effectively what this requires is that
these hydrogen uh ions or which is
really the bare nucleus so they have a
positive charge everything has a
positive charge of those ones is that to
get them to to trigger this reaction
they must approach within distances
which are like the size of the nucleus
itself because the nature in fact what
it's really using is something called
the strong nuclear force there's four
fundamental forces in the universe this
is the strongest one but it has a
strange property is that it while it's
the strongest force by far it only has
impact over distances which are the size
of a nucleus so to get put that into
what does that mean it's a millionth of
a billionth of a meter okay incredibly
small distances but because the
distances are small and the particles
have charge they want to push strongly
apart namely they have repulsion that
wants to push them apart so it turns
when you go through the math of this the
average velocity or energy of the
particles must be very high to have any
significant probability of the reactions
happening and so the center of our sun
is at about 20 million degrees Celsius
and on Earth this means it's one of the
first things we teach you know entering
graduate students you can do a quick you
can do a quick basically Power Balance
and you can you can determine that on
Earth that it requires a minimum
temperature of about 50 million degrees
Celsius on Earth
to perform Fusion to get enough Fusion
that you would be able to make get
energy gain out of it
so you can trigger Fusion reactions at
lower energy but they become almost
vanishingly small at lower temperatures
than that
first of all let me just link around
some crazy ideas so uh one the strong
force just stepping out and looking at
all the physics
is it weird to you that there's these
forces and they're very particular like
it operates at a very small distance
then gravity operates at a very large
distance and and they're all very
specific in the standard model describes
uh three of those forces extremely well
and there's and this is one of them and
yeah this is one of them and it's just
all kind of works out there's a big part
of you that's uh you know an engineer
that used to step back and almost look
at the philosophy of physics
so it's interesting because as a
scientist I see the universe through
that lens of essentially the interesting
things that we do are through the forces
that are get used around those and
everything works because of that
Richard Feynman had I don't know if
you've ever had Richard fine it's a
little bit of a tangent but she's never
been on the pocket he's never been on
the podcast he was unfortunately passed
away but wanted like a like a hero to
almost all all physicists and then part
of it was because of what you said he
kind of looked through a different lens
at these but typically look like very
dry like equations and relationships and
he kind of I think he brought out the
Wonder of it in some sense right for for
those he posited what would be if you
could write down a single not even
really a sentence but a single concept
that was the most important thing
scientifically that we that we knew
about that in other words you had only
one thing that you could transmit like a
future or past generation it was very
interesting it was um so it's not what
you think it wasn't like oh strong
nuclear force or Fusion or something
like this and it's very profound which
was he was that the reason that matter
operates the way that it does is because
all matter is made up of individual
particles that interact each other
through forces that was it so just that
atomic theory basically yeah
which is like wow that's like so simple
but it's not so simple it's because like
who thinks about atoms that they're made
of like I I this is a good this is a
good question I give to my students how
many atoms are in your body like almost
no students can answer this but to me
that's like a fundamental thing by the
way it's about 10 to the 28. out of 28.
so that's uh you know trillion or you
know million trillion trillion or
something like that yes so one thing is
to think about the number and the other
is to start to really Ponder the fact
that it all holds together yeah it all
holds together and you're actually that
you're more that than you are anything
else yes exactly yeah no I mean there
are people who do study such things of
the fact that if you look at the for
example the ratios between those
fundamental forces people have figured
out oh if this ratio was different by
some Factor like a factor of two or
something I was like oh this would all
like not work and I look you look at the
sun right it's like so it turns out that
there are key reactions that if they had
slightly lower or probability no star
would ever ignite and then life wouldn't
be possible it does seem like the
universe set things up for us that it's
possible to do some cool things but it's
challenging so that that keeps it fun
for us yeah yeah that's the way I look
at it I mean the you know the Multiverse
model is an interesting one uh because
there are you know Quantum scientists
who look at and figure I was like oh
it's like oh yeah like Quantum science
perhaps tells us that there are almost
an infinite you know variety of other
universes but the way that it works
probably is it's almost like a form of
natural selection it's like well the
universes that didn't have the correct
or interesting relationships between
these forces nothing happens in them so
almost by definition the fact that we're
having this conversation means that
we're in one of the interesting ones by
default
yeah one of the somewhat interesting but
there's probably super interesting ones
we I I tend to think of humans as
incredible creatures our brain is is an
incredible Computing device but
I think we're also extremely cognitively
limited I can imagine
alien civilizations that are much much
much much more intelligent uh in ways we
can't even comprehend in terms of their
ability to come to construct models of
the world and to do physics to do
physics and Mathematics I would see it
in a slightly different way it's
actually it's because we have
um we have we have creatures that live
with us on the earth that have cognition
right that understand and move through
their environment but they they actually
see things in a way or they sense things
in a way which is so fundamentally
different it's really hard like the TR
it's the problem is the translation not
necessarily intelligence so it's the
perception of the world so I have a dog
and when I go out and I see my dog like
smelling things there's a realization
that I have that he sees or senses the
world in a way that I can never like I
can't understand it because I can't
translate my way to this we get little
glimpses of this as humans though by the
way because there are some parts of it
for example Optical information which
comes from light isn't now because we've
developed the technology we can actually
see things you know I've had I get this
you know as a one of my areas of
research is spectroscopy so this means
the study of light you know and I and I
get this quote unquote see things or
representation of them from you know the
far infrared all the way to like hard
hard x-rays which is several orders of
magnitude of the of the light intensity
but our own human eyes like see a teeny
teeny little sliver of this yeah so that
even like bees for example see a
different place than we do so I don't I
I think if you think of there's already
other intelligences like around us in a
way in a limited way
um because of the way they can
communicate but it's like those are
already baffling in many ways yeah so if
we just focus in on the senses there's
already a lot of diversity but there's
probably things we're not even
considering as possibilities for example
uh whatever the heck Consciousness is
could actually be a door into
understanding some physical phenomena
we're not I haven't even begun
understanding so just like you said
spectroscopy there could be a similar
kind of spectrum for Consciousness that
we're just like we're like these dumb uh
the descendants of Apes like walking
around it sure feels like something to
experience the color red but like we
don't have
it's the same as in the ancient times
you experience physics you experience
light it's like oh it's bright and you
know yeah yeah and you construct kind of
uh what's interesting we might actually
experience this faster than we thought
because we might be building another
another kind of intelligence yeah and
that that intelligence will explain to
us how silly we are there was an email
thread going around the professors in my
department already of uh so what is it
going to look like to figure out if
students have actually written their
term papers or it's chat
chat GPT
um uh it was so as usual as it is where
you we tend to be empiricists in my
field so of course they were in there
like trying to figure out if uh if it
could answer like questions for a
qualifying exam to get into the PHD
program
T which was it they didn't do that well
at that point but of course this is just
the beginning of it so we have some
interesting ones to go eventually both
the students and the professors will be
replaced by Chad GPT yeah and we'll sit
on the beach I really recommend you know
this I don't know if you've ever seen
them it's called the day the universe
changed
James Burke he's a science historian
based in the UK um he had a had a fairly
famous series on on public television
called connections I think it was but
the one that I really enjoyed was the
day the universe changed and the the
reason for the title of it was that
um he says the universe is what we know
and perceive of it so when there's a
fundamental insight as to something new
the universe for us changes of course
the universe from an objective point of
view is the same as it was before but
for us it has changed so he walks
through these these moments of
perception in in in in the history of
humanity that like changed what we were
right and so as I was thinking about
coming to to discuss this you know
people see Fusion oh it's still far away
or we've been it's been slow progress
It's like when my when my godmother was
born like people had no idea how Stars
worked
so you talk about like that day that
Insight the universe changed it's like
oh this is the I mean and they still
didn't understand all the parts of it
but you know they basically got it it's
like oh because of the because of the
understanding of these processes it's
like we unveiled the reason that there
can be life in the universe that's
probably one of those days the universe
changed right yeah and uh remember 1930s
yeah it seems like technology is
developing faster and faster and faster
I tend to think just like with your gbt
I think this year might be extremely
interesting just with how rapid and how
profitable the efforts and artificial
intelligence are that just stuff will
happen where our whole world is
transformed like this
and we're there's a shock and then next
day you kind of go on and you adjust
immediately uh you probably won't have a
similar kind of thing with uh nuclear
fusion with energy because there's
there's probably going to be an opening
ceremony and stuff yes an announcement
it'll take months but with uh with
digital technology you can just have a
immediate transformation of society and
then it'll be this gasp and then you
kind of adjust like we always do and
then you don't even remember just like
with the internet and so on how the days
were before and how did it worked before
right yeah I mean Fusion will be because
it's energy it's it's nature is that it
will be um and anything that has to do
with energy use tends to be a slower
transition but they're the most I would
argue for some of the most profound
transitions that we make I mean the
reason that we can live like this and
sit in this building and have this
podcast and people around the world is
is at its heart is energy use and it's
intense energy use that came from the
evolution of starting to use intense
Energies at the beginning of the
Industrial Revolution up to now it's
that it's like it's a Bedrock actually
of all of these but it doesn't tend to
come overnight yeah and some of the most
important some of the most amazing
Technologies one we don't notice because
we take it for granted because it
enables this whole thing yeah which is
energy which is amazing for how
fundamental it is to our society and way
of life is a very poorly understood
concept actually just even energy itself
people confuse energy sources with
energy storage with energy transmission
these are different physical phenomena
which are very important for so for
example
you know you buy an electric car and you
go oh good I have an emission free car
and uh ah but it's like so so why do you
say that well it's because if I draw the
circle around the car I have electricity
and it doesn't emit any anything okay
but you plug that into a grid where you
follow that wire back there could be a
coal power plant or a gas power plant at
the end of that oh really I mean so this
isn't like carbon free oh
and it's not their fault it's just you
know they don't like the car isn't a
source of energy the underlying source
of energy was the combustion of the fuel
back somewhere plus there's also a story
of how the raw materials are mined in
which parts of the world uh with sort of
basic respect or or deep disrespect of
human rights that happens in that money
so the whole supply chain there's a
story there that's deeper than just the
particular electric car with a circle
around it in the physics or the science
of it too is the energy use that it
takes to do that digging up which is
also important and all that yeah anyway
so yeah we wandered away from Fusion but
yes it's beautiful but it's very
important actually to in the in the
context of this just because you know
those of us who work in infusion and
these other kinds of
um sort of disruptive Energy
Technologies it's it's interesting I do
think about like what would it what is
it going to mean to society to have an
energy source that is like this that
would be like you know which has which
is such completely different
characteristics
for example you know free unlimited
access to the fuel but it has technology
implications so what does this mean
geopolitically what does it mean for how
we how we distribute wealth within our
society it's
it's very difficult to know but probably
profound yeah we're gonna have to find
another reason to start wars uh for
instead of resources we've done a pretty
good job of that over the course of our
histories yeah uh so we talked about the
forces of physics and again sticking to
the philosophical before we get to the
specific technical stuff E equals MC
squared you mentioned how amazing is
that to you that energy and mass are the
same
and what does that have to do in your
clear Fusion
so it has to do with everything we do
it's the fact that energy and mass are
equivalent to each other they're just
the way we usually comment to it is that
they're Just Energy just in different
forms can you intuitively understand
that yes but it takes a long time I
um having for all but usually often I've
I teach the um the introductory class
for incoming nuclear engineers and and
so we put this up as an equation and we
go through many iterations of using this
uh to how you derive it how you use it
and so forth and then you usually in the
final exam I would give I would
basically take all the equations that
I've used before and I flip it around I
basically instead of thinking about
energy is equal to mass is sort of mass
is equal to energy and I asked the
question in a different way and usually
about half the students don't get it it
takes a while is to get that intuition
yeah
um so so in the end it's interesting is
that this is is actually the source of
all free energy because that energy that
we're talking about is kinetic energy if
it can be transformed from Mass so it
turns out even even though we we used
equals MC square this is burning coal
and and burning gas are and burning wood
is actually still equals mc squared the
problem is that you would never know
this because the relative change in the
mass is incredibly small by the way
which comes back to Fusion which is that
E equals m c squared okay so what does
this mean it tells you that the the
amount of energy that is liberated in a
particular reaction when you change Mass
has to because c squared is that's the
speed of light squared it's a large
number it's a very large number and it's
totally constant everywhere in the
universe which is which is another weird
thing which is another weird thing and
in all rest frames and the actually the
relatively stuff gets more
difficult conceptually even until you
get through it anyway so you go you go
to that and and it's in what that tells
you is that it's the relative it's the
relative change in the mass we'll tell
you about the relative amount of energy
that's liberated and this is what makes
fusion and you asked about Fusion as
well too this is what makes them
extraordinary it's because the relative
change in the mass is very large as
compared to what you get like in a
chemical reaction in fact it's about
it's about 10 million times larger
and that is at the heart of why you use
something like Fusion it's because that
is a fundamental of nature like you
can't beat that so of whatever you do if
you're thinking about and why do I care
about this well because Mass is like the
fuel right so this means Gathering the
resources that it takes to gather a fuel
to hold it together to deal with it the
environmental impact it would have and
fusion will always have 20 million times
the amount of energy we lease per
reaction that you could have those so
this is why you know we consider it the
ultimate like environmentally friendly
energy source is because of that so is
it is it correct to think of mass
broadly as a kind of storage of energy
yes
you mentioned it's environmentally
friendly so
nuclear fusion is a source of energy
it's cheap Clean safe so easy access to
fuel and virtual Unlimited Supply no
production of greenhouse gases little
radioactive waste produced allegedly uh
can you can you sort of elaborate why
it's cheap clean and safe I'll start
with the easiest one cheap it is not
cheap yet because it hasn't been made at
a commercial scale right flies when
you're having fun yes yeah yeah
but yes not yet but we'll talk about it
actually we'll we'll come back to that
because it it this is cheaper or or a
more technically correct term that is
economic that it's economically
interesting is is really the primary
challenge actually a fusion at this
point
um but really we can get back to that so
what were the other ones you said um so
cheap actually when we're talking about
cheap we're thinking like asymptotically
like if you take it Forward yeah several
hundred years uh that's sort of because
of how much availability there is of
resources to use of the fuel you have
the fuel we should separate those two
the fuel will all the fuel is already
cheap it's basically free right what do
you mean by basically free so if if we
were to be using fusion
um fuel sources to power your and it's
like that's all we have is fusion power
plants around and we were doing it the
fuel cost per person or something like
10 cents a year it's like it's free okay
this is why it's hard to in some ways I
think it's hard to understand Fusion
because people see this and go oh if the
fuel is free this means the energy
source is free because we're used to
energy sources like this so we you know
we spend resources and drill to get gas
or oil or we chop wood or we make coal
we find coal or these things all right
so Fusion this is what makes fusion and
it's also
um it's not an intermittent renewable
energy source like wind and solar so say
but this is this makes it hard to
understand so as you're saying the fuel
is free why isn't the like why isn't the
energy source free and it's because of
the necessary Technologies which must be
applied to basically recreate the
conditions which are in stars in the
center of stars in fact so there's only
one natural place in the universe that
fusion fusion energy occurs that's in
the center of stars so that's going to
bring a price to it depending on the the
cost and sorry the size and complexity
of of the technology that's needed to
recreate those things and we'll talk
about the details of double Technologies
and which parts might be expensive today
and which parts might be expensive in
200 years exactly it will have a
revolution I'm certain of it um so about
clean so clean is at its heart what it
does is convert it basically converts
hydrogen into it's it's it's heavier
forms of hydrogen the one the most
predominant one that we use on Earth and
converts it into helium and some other
products but primarily helium is the
product that's left behind so helium
safe inert gas you know in fact that's
actually what our sun is doing is
eventually going to extinguish itself
because it'll just make so much helium
that it doesn't it doesn't do that so in
that sense clean because there's no
there's no emissions of of carbon or
pollutants that come directly from the
combustion of the fuel itself and safe
safe
we're talking about very high
temperatures yeah yeah so this is also
the counterintuitive thing so you I told
you temperatures which like 50 million
degrees or it actually tends to be more
like about 100 million degrees is really
what we aim for so how can 100 million
degrees be safe and it's safe because it
is
this is so much hotter than anything on
Earth where everything on Earth is at
around 300 Kelvin you know it's around a
few tens of degrees Celsius
and what this means is that in order to
get a medium to those temperatures you
have to completely isolate it from
anything to do with terrestrial
environment it can have no contact like
with anything on Earth basically so this
means what we this is the technology
that I just described is it
fundamentally what it does is it takes
this Fuel and uh it isolates it from any
terrestrial condition so that it has no
idea it's on Earth it's not touching any
object that that's at room temperature
including the walls of the containment
even including the walls of the
containment building or containment
device or even air or anything like this
so so it's that part
um that makes it safe in this and
there's there's actually another aspect
to it but that that fundamental part
makes it so safe
um in in the main lines
approach diffusion is also that it's
very hot but there's very very few
particles
in at any time in in the thing that we
view the power plant and the actually
the more correct way to do it is you say
there's very few particles per unit
volume so in a cubic centimeter and
cubic meter or something so we can do
this so right now we're although we
don't think of air really as there's
atoms floating around us and there's a
density because if I wave my hand I can
feel the air pushing against my face
that means we're in a fluid or a gas
which is around us that has a particular
number of atoms per cubic meter right so
it's about this actually turns out to be
10 to the 25th so this is one with 25
zeros behind it per cubic meter so we
can figure out like cubic like cubic
meters about like this yeah the volume
of this table like the whole volume
um okay very good so like Fusion there's
a few of those so Fusion like the
mainstream one of fusion like what we're
working on at MIT will have a hundred
thousand times less particles
per unit volume than that so this is
very interesting because it's
extraordinarily Hot 100 million degrees
but it's very tenuous
and what matters from the engineering
and safety point of view is the amount
of energy which is stored per unit
volume because this tells you about the
the scenarios and that's what you worry
about because when those kinds of
energies are released Suddenly It's like
what would be the consequences right so
the consequences of this are essentially
zero because that's less energy content
than boiling water
because of the low density because of
the low density so if you take water is
at about 100 million to a billion times
more dense than this so even though it's
at much lower temperature it's actually
still it has more energy content so if
for this reason
um you know one of the ways that I
explain this is that if you imagine a
power plant that's like powering
Cambridge Massachusetts like if you were
to which you you wouldn't do this
directly but if you went like this on it
it actually extinguishes the fusion
because it gets too cold immediately
yeah so that's the other one and the
other part is that it does not and
because it works by staying hot rather
than a chain reaction it can't run out
of control that's the other part of it
so by the way this is what very much
distinguishes it from fission it's not a
process that can run away from you
because it's it's basically thermally
stable
what does thermostable mean that means
is that you want to run it at the
optimization in temperature such that if
it deviates away from that temperature
the reactivity gets lower and and the
reason for this is because it's hard to
keep the reactivity going like it's a
very hard fire to keep going basically
also it doesn't it doesn't run away from
you it can't run away how difficult is
the control there to keep it at that it
varies from from concept to concept but
in generally it's fairly it's fairly
easy to do that and the easiest thing it
can't it can't physically run away from
you because the other part of it is that
there's just at any given time there's a
very very small amount of fuel available
to fuse anyway so this means that that's
always intrinsically limited to this so
if it even if the power consumption of
the device goes up it just kind of burns
itself out immediately yeah so you are
the just to take a tan another tangent
on tangent you're the director of mit's
plasma science at Fusion Center uh
we'll talk about maybe you can mention
some interesting aspects of the history
of the center in the broader history
of uh MIT maybe brought a history of
Science and Engineering in the history
of human civilization but also just the
link on the safety aspect you know
um
how do you prevent you know some of the
amazing reactors that you're designing
how do you prevent from destroying all
of human civilization in the process
what's the safety protocols Fusion is
um interesting because it's not really
directly weaponizable because what I
mean by that is that you have you have
to work very hard to make these
conditions and which you can get energy
gain from from fusion
um and uh this means that the the when
we design these devices with respect to
application in the energy field is that
they you know you
the while while they will because
they're producing large amounts of power
and they will have hot things inside of
them this means that they have like a
level of industrial Hazard which is very
similar to like you would have like in a
chemical processing plant or anything
like that any kind of energy plant
actually has these as well too
but the underlying under underneath the
core technology like can't be directly
used uh in in a nefarious way because of
the power that's being emitted it just
basically will if you try to do those
things typically it just stops working
so the safety concerns have to do with
just regular things that uh like
equipment malfunctioning
uh melting of equip like all this kind
of stuff that yeah it has nothing to do
with Fusion necessarily yeah I mean
usually what we worry about is the
viability because in the end we build
pretty complex objects to realize these
requirements and so what we try really
hard to do is like not damage those
components which but those are things
which are internal to the to the fusion
device and and it's this is not
something that you would
um consider about like it would as you
say destroy human civilization because
that release of energy is just
inherently limited because of the fusion
process so it doesn't say that there's
zero so you asked about the other
feature for that it's safe so it is the
process process itself is intrinsically
safe but because it's a complex
technology you still have to take into
account consideration aspects of the
safety so it produces ionizing radiation
instantaneously so you have to take care
of this which means that you Shield it
you think of like your dental X-rays or
or treatments for cancer and things like
this we we always Shield ourselves from
this so we get the beneficial effects
but we minimize the harmful effects of
those so there are those aspects of it
as well too yeah so we'll return to
mit's plasma science the future Center
but let us Linger on the uh destruction
of human civilization uh which brings us
to the topic of nuclear fission what is
that so the the process that is inside
nuclear weapons and current nuclear
power plants so it relies on the same
underlying physical principle but it's
exactly the opposite a few which
actually the names imply Fusion means
bringing things together fission means
splitting things apart so fission
requires the heaviest instead of the
lightest and the most unstable versus
the most stable uh elements so this
tends to be uranium or plutonium
primarily uranium so take uranium so
uranium-235 is one of the that this is
one of the heaviest unstable elements
and what happens is that this is a
fission is triggered by the fact that
one of these subatomic particles the
neutron which has no electric charge
basically gets in proximity enough to
this and and triggers an instability
effectively inside of this what is
teetering on the border of instability
and basically splits it apart
and that's the fission right the
fissioning
um and so when that happens because the
products that are and kind of roughly
splits in two but it's not even that
it's actually more complicated splits
into this whole array of lighter
elements and nuclei and when that
happens there's less rest Mass
uh uh laugh than the original one so
it's actually the same so it's again
it's rearrangement of the strong nuclear
force that's happening
um but that's the source of the energy
and so in the end it's like so this is a
famous graph that we show everybody is
is basically it turns out every element
that exists in the periodic table all
the things that make up everything have
uh have a remember you asked a good
question it was like so should we think
of mass as being the same as stored
energy yes so you can make a plot that
basically shows the relative amount of
stored energy in all of the elements
that are stable and make up basically
the world okay in the universe and it
turns out that this one has a maximum
amount of of stability or storage at
iron
so it's kind of in the middle of the
periodic table because this goes from
you know it's roughly that and so this
what that means is that if
um if you take something heavier than
iron like uranium which is which is more
than twice as heavy than that and you
split apart if you somehow just
magically you just split apart as
constituents and you get something
that's latter that will because it moves
to a more stable energy state it
releases kinetic energy that's the
energy that we use kinetic energy
meaning the movement of things so it's
actually an energy you can do something
with and fusion sits on the other side
of that because it's also moving towards
iron but it's do it has to do it through
Fusion together so this leads to some
pretty profound differences as I said
they have some underlying physics or
science
um uh proximity to each other but
they're literally the opposite so Fusion
why is this it actually goes into
practical implications of it which is
that fission can happen at room
temperature
it's because there's this neutron has no
electric charge and therefore it's
literally room temperature neutrons that
actually trigger the reaction so this
means
um in order to establish uh what's going
on with it and it works by a chain
reaction is that you can do this at room
temperature so Enrico Fermi did this
like on a on a University campus
University of Chicago campus the first
sustained you know chain reaction was
done underneath the squash court
with a big blocks of graphite you know
it was still don't get me wrong an
incredible human achievement right but
that's you know and then you think about
Fusion I have to build a Contraption of
some kind that's going to get to 100
million degrees okay wow that's a big
difference the other one is about the
chain reaction that namely fission works
by the fact that when that fission
occurs it actually produces free
neutrons free neutrons particularly if
they get slowed down to room temperature
trigger can trigger other fission
reactions if there's other uranium
nearby or physometers so this means that
the way that it releases energy is that
you set this up in a very careful way
such that every on average every
reaction that happens exactly releases
enough neutrons and slows down that they
actually make another reaction one
exactly one and what this means is that
because each reaction releases a fixed
amount of energy you do this and then in
time this looks like just a constant
power output so that's how our fission
power plant works and so either the
control of the the chain reactions is
extremely difficult and extremely
important for it's very important and
when you intentionally design it that it
creates more than one fission reaction
per per starting reaction that it
exponentiates away
but which is which is what a nuclear
weapon is yeah so how does an atomic
weapon work how does a hydrogen bomb
work asking for a friend yeah
yeah so um at its heart what it how what
you do is you very quickly put together
enough of these materials that can
undergo fission with room temperature
neutrons and you put them together fast
enough that what happens is that this
process can essentially grow
mathematically like very fast and so
this releases large amounts of energy so
that's the underlying reason that it
works
so you've heard of a fusion weapon so
this is interesting is that it is it but
it's dislike Fusion Energy in the sense
that what happens is that you're using
Fusion reactions to but it's simply it
increases the gain actually of the
weapon rather than
um it's it's not a pure at its heart
it's still a fission weapon you're just
using Fusion reactions as a sort of
intermediate Catalyst basically to get
even more energy out of it
but it's not directly applicable to to
be used in an energy source does it
terrify you just again to step back at
the philosophical that humans have been
able to use physics and
uh engineering to create such powerful
weapons
I wouldn't say terrify I mean we should
be
this is the this is the progress of
human every time that we've gone access
you talk again you know the day the
universe changed those really changed
when we got access to new kinds of
energy sources but every time you get
acts and typically what this meant was
you get access to more intense energy
right that's and that's what that was
and so the ability to move from burning
wood to using coal to using gasoline and
petrol and then finally to use this is
that
is that both the potency and the
consequences are elevated
around those things it's just like you
said the
the way that Fusion nuclear fusion would
change the world
I don't think unless we think really
deeply we'll be able to anticipate some
of the things we can create there's
going to be a lot of amazing stuff but
then that amazing stuff is going to
enable more amazing stuff and more
unfortunately or uh depending how you
see on it more powerful weapons well
yeah but see that's the thing Fusion
breaks that Trend in the following way
so one of them so Fusion doesn't work on
a chain reaction
there's no Chain Reaction zero so this
means it cannot physically exponentiate
away on you because it works and
actually this is why Star by the way we
know this already it's why stars are so
stable why most stars and suns are so
stable it's because they are regulated
through their own temperature and their
Heating
because what's happening is not that
there's some probability of this
exponentiating away is that the energy
that's being released by Fusion
basically is keeping the fire hot
and these tend to be you know and when
it comes down to thermodynamics and
things like this there's a reason for
example it's pretty easy to keep of
constant temperature like in an oven and
things like this it's the same thing
infusion so this is actually one of the
features that I would argue Fusion
breaks the breaks the trend of this is
that it's it has more energy intensity
than than fission on on paper but it
actually does not have the consequences
of control and sort of Rapid Release of
the energy because it's actually it the
physical system just doesn't want to do
that yeah we're gonna have to look
elsewhere for the weapons with which we
fight World War III
fair enough uh so
what is plasma that you may may have not
mentioned you mentioned ions and
electrons so what is plasma what is the
role of plasma and nuclear fusion so
plasma is a phase of matter or state of
matter so
unfortunately our schools don't it's
like I'm not sure why this is the case
but all all children learn the three
phases of matter right so and what does
this mean so we'll take like Waters an
example so if you if it's cold it's ice
it's in a solid phase right and then if
you heat it up the temp it's the
temperature that typically depends sets
the phase although it's not it's not
only temperature so you heat it up and
you go to a liquid and obviously it
changes its physical properties because
it can you can pour it and so forth
right and then if you heat this up
enough it turns into a gas and a gas
behaves differently because there's a
very Sudden Change in the density
actually that's what's happening so it
changes by about a factor of ten
thousand in density from the from the
liquid phase into when you make it into
steam atmospheric pressure all very good
except the problem is they forgot like
what happens if you just keep elevating
the temperature you don't want to give
kids ideas they're going to start
experimenting they're going to start
heating up the gas it's good to start
doing anyway so you
um it turns out that once you get above
it's approximately five or ten thousand
degrees Celsius then you hit a new phase
of matter and actually that's the phase
of matter that is for all pretty much
all the temperatures that are above that
as well too
um and so what does that mean so it
actually changes phase so it's a
different state of matter and the reason
that it becomes a different state of
matter is that it's hot enough that what
happens is that the atoms that make up
remember go back to Feynman right
everything's made up of these individual
things these atoms but atoms can
actually themselves be
um which are which are made of nuclei
which contain the positive particles and
the neutrons and then the electrons
which are very very light very much less
mass than than the nucleus and that
surround this this is what makes up an
atom so a plasma is what happens when
you start pulling away enough of those
electrons that they're free from the ion
so almost all the atoms that make up us
up and this water and all that the
electrons are in tightly bound States
and basically they're extremely stable
once you're about five thousand or ten
thousand degrees you start pulling off
the electrons and what this means is
that now the medium that is there its
constituent particles have mostly have
net charge on them
so why does that matter it's because now
this means that the particles can
interact but through their electric
charge in some sense they were when it
was in the atom as well too but now that
they're free particles this means that
they start it fundamentally changes the
behavior it doesn't behave like a gas it
doesn't behave like a solid or a liquid
I mean he's like a plasma right and so
why is this why is it disappointing that
we don't speak about this it's because
99 of the universe is in the plasma
State it's called Stars
and in fact our own Sun at the center of
the sun is what clearly a plasma but
actually the surface of the sun which is
around 5500 Celsius is also a plasma
because it's hot enough that is that in
fact the things that you see sometimes
you see these pictures from the surface
of the Sun amazing like Satellite
photographs of like those big arms of
things and of light coming off of the
surface of the Sun and solar flares
those are plasmas what are some
interesting ways that this forced state
of matter is different than gas
let's go to how a gas works right so the
reason a gap and it goes back to
fireman's Brilliance and saying that
this is the most important concept the
reason actually solid liquid and gas
phases work is because the the nature of
the interaction between the atoms
changes and so in a gas you can think of
this as being this room and the things
although you can't see them is that the
molecules are flying around but then
with some frequency they basically
bounce into each other and when they
bounce into each other the exchange
momentum and energy around on this
and so it turns out that the probability
and the distances and the scattering of
those of what they do it's it's those
interactions that set the uh about how a
gas behaves so what do you mean by this
well so for example if I take a a an
imaginary test particle of some kind
like I spray something into the air
that's got a particular color in fact
you can do it in liquids as well too
like how it gradually will disperse away
from you this is this is fundamentally
set because of the way that those
particles are bouncing into the
probabilities of those uh the rate that
they go at and the distance that they go
out and so forth so this was figured out
by Einstein and others at the beginning
of the Browning motion all these kinds
of things these are these were set um up
at the beginning of the last century and
it was really like this great Revelation
wow this is why matter behaves the way
that it does like wow
um
um so but it's really like and also in
liquids and in solids like what really
matters is is is is is how you're
interacting with your nearest neighbor
so you think about that one the gas
particles are basically going around
until the until they actually hit into
each other though they don't really
exchange information and it's the same
in a liquid you're kind of beside each
other but you can kind of move around in
a solid you're literally like stuck
beside your neighbor you can't move like
yeah
plasmas are are weird in the sense is
that they're it's not like that so and
it's because the particles have electric
charge this means that they can push
against each other without actually
being in close proximity to each other
it's not that's not an infinitely true
statement which we go together it's a
little bit more technical but basically
this means that you can start having
action or exchange of information at a
distance
and that's in fact the definition of a
plasma that it says these have a
technical name is called a coulomb
collision it just means that it's
dictated by this Force which is being
pushed between the charged particles is
that the definition of a plasma is a is
a medium in which the collective
behavior is dominated by these
collisions at a distance
so you can imagine then this starts to
to give you some Strange Behaviors
um uh which I could I could quickly talk
about like for example one of the most
counterintuitive ones is as plasmas get
more hot as they get higher in
temperature then the collisions happen
less frequently
it's like like what that doesn't make
any sense when particles go faster you
think they would Collide more often
but because the particles are
interacting through interacting through
their electric field when they're going
faster they actually spend less time in
the influential field of each other and
so they talk to each other Less in an
energy and momentum exchange point of
view it's just one of the count one of
the counter-intuitive aspects of plasmas
which is probably very uh relevant for
nuclear fusion yes exactly so if I can
try to summarize
what a nuclear fusion reactor is
supposed to do
so you have what a couple of elements
what are usually the elements usually
deuterium and tritium which are the
heavy forms of hydrogen hydrogen you
have those and you start heating it
and then as you start heating it I
forgot the temperature you said about
100 million no first first it becomes oh
first it becomes a plastic so it's a gas
and then it turns into a plasma at about
10 000 degrees and then so you have a
bunch of electrons and ions flying
around and then you keep heating the
thing
and uh I guess as you heat the thing the
ions hit each other rarer and rarer Yes
except oh man that's not fun so you have
to keep heating it
um such that uh you have to keep hitting
into the probability of them colliding
becomes reasonably high and so and also
on top of that I'm sorry to interrupt
you have to prevent them from hitting
the walls of the reactor that's exactly
somehow so you asked about the the
definitions of the requirements for
Fusion so the most famous one or some
sense the most intuitive one is the
temperature and the reason for that is
that you you can make many many kinds of
plasmas that have zero Fusion going on
in them and the reason for this is that
the average so I mean you can make a
plasma at around 10 000 in fact if you
come by the way you're welcome to come
to our laboratory at the psfc I can show
you a demonstration of a plasma that you
can see with your eyes instead of about
10 000 degrees and you can put your hand
up beside it and all this and it's like
and nothing there's zero Fusion going on
so you have uh so what was the
temperature of the plasma about ten
thousand degrees you can stick your hand
in well you can't stick your hand into
it but there's a glass tube you can
basically see this yeah yeah and you can
put your hand on the glass too because
it's what's the colors of purple it's
yeah it's purple yeah
it is it is kind of beautiful
um yeah plasmas are actually quite uh
astonishing sometimes in their beauty
actually one of the most amazing forms
of plasma is Lightning by the way which
is is instantaneous form of plasma that
exists on Earth but immediately goes
away because everything else around it
it's at room temperature
yeah so there's different requirements
in this so making a plasma takes
about this but at 10 000 degrees even at
a million degrees there's almost no
probability of the fusion reactions
occurring and this is because while the
the charged particles can hit into each
other if you go back to the very
beginning of this remember I said oh
these charged particles have to get to
within distances which are like this
size of a nucleus because of the strong
nuclear force well
unfortunately as the particles get
closer this the repulsion that comes
from the charge the coulomb force
increases like the inverse distance
squared I don't know so as they get
closer they're pushing harder and harder
apart
so then then it gets a little bit more
exotic which you maybe you'll like
though that it turns out that you people
understood this and um at the beginning
of the uh of of the age of after
Rutherford discovered the nucleus it's
like oh yeah I was like how are we going
to how's this going to work right
because how do you get anything within
these distances it's a good inquire
extraordinary energy and it does and in
fact when you look at those energies
they're very very high
um but it turns out quantum physics
comes to the rescue
because the particles aren't aren't
actually just particles they're also
waves this is the point of quantum right
the you can treat them both as waves and
as as particles and it turns out if you
get if they get in close enough
proximity to each other then the
particle pops through basically this
energy barrier through an effect called
Quantum tunneling which is really just
the transposition of the fact that it's
a wave so that it has a finite
probability of this it's it's this by
the way you talk about like do you have
a hard time like conceptualizing this
these are this is one of them yeah this
is like throwing a ping-pong ball like
at a a piece of paper and then every
like you know 100 of them just like
magically show up on the other side of
the paper without seemingly breaking the
paper I mean to use a physical analogy
yeah that's phenomena is important is uh
critical for the function of nuclear
fusion yeah all kinds of fusions so this
this is the reason why Stars can work as
well too like the stars would have to be
much much hotter actually to be able to
in fact it's not clear that they would
actually ignite in fact without this
effect and so we get to that so this is
why there's another requirement it's
it's not so you must make a plasma but
you also also must get it very hot in
order for the reactions to have a
significant probability to actually fuse
and it actually falls effectively almost
to zero for lower temperatures as well
too so there's some nice equation yes
that gets you to 50 million degrees
or like uh yeah the or that you said
practically speaking 100 million so it's
a really simple equation it's the ideal
gas law basically almost so it's in the
end you've got a certain number of
particle of these Fusion particles in
the plasma state they're in the plasma
State there's a certain number of
particles and if the confinement is
perfect if you put in a certain content
of energy then basically eventually they
just they come up in a temperature and
they become they they go up they go up
to high temperature this turns out to be
by the way extraordinarily small amounts
of energy
and you go what it's like I'm getting
something to like 100 million degrees
that's gonna take the biggest flame
burner that I've ever seen no
and the reason for this is it goes back
to the energy content of of this so yeah
you have to there's you have to get it
to high average energy but there's very
very few particles this is low density
low density in the reactor is this so
you the way that you do this is
primarily again this is not exactly true
in all kinds of fusion but in the in the
primary one that we work on a magnetic
Fusion this is all happening in a hard
vacuum so it's like it's happening in
outer space so basically you've gotten
rid of all the other particles except
for these specialized one at a time uh
no actually it's even easier than that
you you connect a gas valve and you
basically leak gas into it in a
controlled fashion yeah yeah well this
is beautiful the gas cylinder how do you
get it from hitting the walls yeah so
now you've touched on the other
necessary requirements so it turns out
it's not just temperature that's
required you must also confine it
so what does this mean confine it and
there's two types of confinement as you
mentioned you mentioned the magnetic one
magnetic one and there's another one
called inertial as well too but the
general principle actually has nothing
to do with in particular with what your
what with the technology is that you use
to confine it it's because
this goes back to the fact that the
requirement in this is high temperature
and thermal content so it's like
Building A Fire Man and what this means
is that if you when you release the
energy into this or or apply heat to
this if it just instantly leaks out it
can never get hot right so you're
familiar with this it's like you've got
something that you're you're trying to
apply heat to but you're just throwing
the heat away very quickly this is why
we insulate homes by the way and things
like those right it's like you don't
want the heat that's coming into this
room to just immediately leave because
you'll just start consuming infinite
amounts of heat to try to keep it hot so
in the end this is one of the
requirements and it actually has a name
we call the energy confinement time so
this means if you release a certain
amount of energy into this fuel
um kind of how long you sit there and
you look at your watch how long does it
take for this energy to like leave the
system so you could imagine that in this
room that you know these heaters are
putting energy into the air in this room
and you waited for a day a but all the
Heat have gone to outside if I open up
the windows oh there that's energy
confinement time okay so it's the same
concept as that so this is an important
one so all Fusion must have confinement
uh there's another more esoteric reason
for this which is that people often
confuse temperature and energy
so what I mean by that so this is
literally a temperature which means that
it is a system in which all the
particles every particle has high
kinetic energy and is actually in a
fully relaxed State namely that entropy
has been maximized and it gets a little
bit more technical but this means that
basically it is it is a thermal system
so it's like the air in this room it's
like the water it's the water in this
these all have temperatures which means
that there's a distribution of those
energies because the particles have
collided so much that it's there so we
this is distinguished from having high
energy particles like what we have in
like particle accelerators like CERN and
so forth those are high kinetic energy
but it's not a temperature so it
actually doesn't count as confinement so
we go through all of those you have
temperature
um and then the other requirement not
too surprising is actually that there
has to be enough density of the fuel
enough but enough but not too much yes
and so in the end
um the way that it there's a fancy name
for it it's called The Lawson Criterion
because it was it was it was formulated
by scientists in the United Kingdom
about 1956 or 1957 and this was
essentially the realization of oh this
is what it's going to take regardless of
the confinement method these are this is
the basic what it is actually Power
Balance it just says oh there's a
certain amount of heat coming in which
is coming from the fusion reaction
itself because the fusion reaction heats
the fuel versus how fast you would lose
it and it basically summarizes
summarized by those three parameters
which are fairly simple so temperature
and then the reason we say 100 million
degrees is because almost always in in
for for this kind of fusion deuterium
tritium Fusion the minimum in the
density and the confinement time product
is at about 100 million so you almost
always design your device around that
minimum and then you try to get it
contained well enough and you try to get
enough density so you know so that
temperature thing sounds crazy right
that's what we've actually achieved in
the laboratory like our experiment here
at MIT when it ran it's Optimum
configuration it was at 100 million
degrees
but it wasn't actually the the product
of the density in the confinement time
wasn't sufficient that we were at a
place that we were getting high net
energy gain but it was making Fusion
reactions so this is the sequence that
you go through make a plasma then you
get it hot enough and when you get it
hot enough the fusion reactions start
happening so rapidly that it's
overcoming the the rate at which it's
leaking heat to the outside world and at
some point it just becomes like a star
like a sun and our own our own son and a
star doesn't have anything plugged into
it it's just keeping itself hot through
its own Fusion reactions in the end
that's really close to what a fusion
power plant would look like what does it
visually look like does it does it look
like like you said like purple plasma
you know yeah actually it's it's
invisible to the eye because it's so hot
that it's basically emitting light in
frequencies that we can't detect
it's literally it's invisible
in fact light goes through it visible
light goes through it so easy that if
you were to look at it what you would
see
in in our own particular configuration
what we make is in the end is a donut
shaped um it's a vacuum vessel to keep
the air out of it and when you in when
you turn on the plasma it gets so hot
that most of it just disappears in the
visible spectrum you can't see anything
and there's very very cold plasma which
is between 10 and 100 000 degrees which
is out in the very periphery of it which
is kind of so the very cold plasma is
allowed to interact with the kind of has
to interact with something eventually at
the boundary of the vacuum vessel and
this kind of makes a little halo around
it and it glows this beautiful purple
light basically and these are that's the
um that's the that's what we can sense
in the human Spectrum yeah I I remember
reading on uh subreddit called shower
thoughts
uh which people should check out it's
just fascinating philosophical ideas
that strike you while you're in the
shower and one of them was it's lucky
that a fire when it burns communicates
that it's hot using visible light
otherwise humans would be screwed
um I don't know if there's a deep
profound truth to that but nevertheless
I did find it on shower thought
subreddit actually I do have there this
goes off in a bit of it you're right
this is actually it's interesting
because you know as a scientist you also
think about evolutionary functions and
how we got like why do we have the
senses that we do yes interesting
question right like why can bees see an
UltraViolet and we can't then you go
well it's natural selection for some
reason this wasn't really particularly
important to us right why can't we see
in the infrared and other things can
it's like um
because the people that could it's a
fascinating question right obviously
there's some there's some advantage that
you have there that isn't there and even
color distinguishing right of something
safe to ease not say whatever it would
be uh I actually go back to this because
it's something like that I tell all of
my my students when I'm teaching
um ionizing radiation and radiological
safety whatever you say there's a
cultural concern or that when people
hear the word radiation like what does
this mean it literally just means light
is what it means right but it's light in
different parts of the spectrum right
and so it turns out besides the visible
light that we can see here we are
immersed in almost the totality of the
electromagnetic spectrum there is
visible light there's infrared light
there is microwaves going around as
that's how our cell phone works you
can't it's way past our detection
capability but also higher energy ones
which have to do with ultraviolet light
how you get a sunburn
um and even X-rays and things like this
at small levels are continually being
like from the concrete in this in the
walls of this hotel there's x-rays
hitting our body continuously I can
bring out we can go down to the lab at
MIT can bring out a detector and show
you every single room will have and have
these by our body you mean the 10 to the
28 atoms yeah the 10 to the 28 atoms and
they're coming in and they're
interacting with those things and those
particularly the ones where the light is
at higher average energy per per light
particle those are the ones that can
possibly have an effect on human health
so we we have it's interesting humans
and all animals of
evolved on Earth where we're immersed in
that all the time yeah there's natural
sources of radiation all the time yet we
have zero ability to detect it like zero
yeah and our ability cognitive ability
to filter it all out and not it would
not really overwhelm us actually if we
could see all of it but my main point is
it goes back to your thing about fire
and self-protection if if these ionize
if ionizing radiation was such a
critical aspect of the health of
organisms on Earth we would almost
certainly have evolved methods to detect
it and we have none
and uh yes the physical world that's all
around us yeah you're blowing my mind uh
Dr Dennis white okay let's so you have
experience with Magnetic confinement you
have experience with inertial
confinement most of your work has been a
magnetic economy but let's sort of
um talk about the the the the sexy
recent thing for for a bit of a time
there's been a breakthrough in the news
uh
uh that uh laser-based inertial
confinement was used by Doe's National
ignition facility at the Lawrence
Livermore National Laboratory can you
explain this breakthrough that happened
in December yeah
so it goes to the set of criteria that I
talked about before about getting
high energy gain so in the end
what what are we after in Fusion is that
we we basically assemble this plasma
fuel in some way and we provided a
starting amount of energy think of
lighting the fire and what you want to
do is get back like significant excess
gain from the fact that the fusion is is
making more is releasing the energy so
it's it's like the equivalent of like we
want to have a match a small match light
a fire and then the fire Keeps Us hot
it's like this is very much like that
so as I said we've we've made many of
the and what I mean by we it's like the
fusion Community has pursued aspects of
this through a variety of different
confinement uh methodologies
um is that the
um the key part about what happens
what was the threshold we had never
gotten over before was that if you only
consider the plasma fuel not the not the
total engineering system but just the
plasma fuel itself we had not gotten to
the point yet where basically the size
of the match was was smaller than the
amount of energy that we got from the
fusion is there a good term for when the
output is greater than the input yes yes
it there is well there's several special
definitions of this so one of them is
that if you if you like in a fire if you
light a match and you have it there and
it's an infinitesimal amount of energy
compared to what you're getting out of
the fire we call this ignition which
makes sense right this is like what the
what our own sign is as well too so that
that was not ignition in that sense as
well too so what we call this the
scientific what the one that we I just
talked about which is for for some
instance when I get enough Fusion energy
released compared to the size of the
match we call this sign to Civic break
even break even break even and it's
because you've gotten past the fact that
this is Unity now at this point what is
a fusion gain or as using the notation Q
from the paper overview of the spark
Tacoma before talk using just the same
kind of terms yeah actually so the
technical term is Q capital Q
people actually use Cube we actually use
capital Q or sometimes it's called Q is
taken Q sub P or something like this
okay okay so this is which which means
what what it means is that it's in the
plasma so all we're considering is is
the energy balance or a gain that comes
from the plasma itself we're not
considering the Technologies which are
around it which are providing the
containment and so forth so why why the
excitement and so well because for one
reason it's a rather Sim it's a rather
simple threshold to get over to
understand that you're getting more
energy out from the fusion even the
theoretical sense than you were from the
you know from the starting match do you
mean consent actually simple it's
conceptually simple that you get past
one that everyone under like when you're
less than one that's much less
interesting than getting past one
because that's a really big you started
to get fast but it's it's really it
really is a scientific threshold because
what QP actually
um denotes is the relative amount of
self-heating that's happening in the in
the plasma so what I mean by this is
that in the end in these systems for and
what what you want is something that
where the the relative amount of of
heating which is keeping the fuel hot is
dominated by from the fusion reactions
themselves and and so it becomes it's
it's sort of like thinking like a
bonfire is a lot more interesting
physically than just holding a blow
torch to a wet log right there's a lot
more Dynamics it's a lot more
self-evolved and so forth and what we're
excited as a scientists is that it's
clear that the the in that experiment
that they actually got to a point where
the fusion reactions themselves were
actually altering the state of the
plasma
I was like wow I mean we'd seen it in
glimpses before in magnetic confinement
at relatively small levels but
apparently it seems like in this
experiment it's likely to be a dominant
dominated by self-heating that's a very
important that's a very interesting that
makes it a self-sustaining type of it's
more self-sustaining it's more
self-referential system uh in in a sense
and it sort of self-evolves in a way
again it's not that it's going to evolve
to a dangerous State it's just that we
want to see what happens when when the
fusion is the dominant heating source
and we'll talk about that but so there's
also another element which is the
inertial confinement
uh laser-based initial confinement is
kind of a little bit of another dog okay
so a lot of the broad nuclear fusion
Community has been focused on magnetic
confinement can you explain just how
laser-based inertial confinement works
so it says uh 192 laser beams were
aligned on a deuterium tritium DT Target
smaller than a p yes uh this is like
actually yeah okay well you know it
depends not all P's are made the same
but uh this is like throwing a perfect
strike in baseball from a pitch this is
like a journalist wrote this I think
this is like oh no it's not a journalist
it's do yeah yeah we try to use all
these analogies this is like throwing a
perfect strike in baseball from a
pitcher's Mount 350 miles away from the
plate there you go Department of energy
the United States Department of energy
wrote this
okay so can you explain interesting what
the what the lasers what what actually
happens yeah actually there's usually
Mass confusion about this so
um so what's going on in this form over
so the fuel
is is is delivered in a discrete the
Fusion fuel the deuterium and tritium is
in a discrete spherical it's more like a
BB let's call it a BB so it's a small
one and all the fuel that you're going
to try to to burn is basically there
okay and it's about that size so what's
hap so how are you going to get and it's
that literally it's like at 20 degrees
above absolute zero because the
deuterium and tritium are kept in in a
liquid in a solid state so the fuel is
injected not as a gas as a solid it's
actually and it's very and these are
particular experiments they can
introduce one of these you know these
targets once per day approximately
something like that because it's very
it's very it's kind of amazing
technology actually that I know some of
the people that worked on this uh back
in the is
um they actually make these things out
of BB size of this frozen fuel it's
actually a cryogenic temperatures and
they're almost like Smooth to the atom
level I mean they're amazing pieces of
Technology
so what you do in the end is think what
you have is a spherical
assembly of this fuel like a ball and
what what is the purpose of the lasers
the purpose of the lasers is to provide
Optical energy to the very outside of
this and what happens is the that energy
is absorbed because it's it's in the
solid phase of matter so it's absorbed
really in the surface and then what
happens is that when it's absorbed in
something called the ablator what does
that mean it means it goes instantly
from the solid phase to the gas phase so
it becomes like a rocket engine and but
you hit it like very uniformly so all
there's like rocket engines coming off
this surface think of like an asteroid
almost where there's like rockets coming
off and all this thing so what does that
do what does a rocket do it actually
pushes by Newton's Laws right it pushes
the other thing on the other side of it
equal and opposite reaction it pushes it
in so what it does is it that the lasers
actually don't Heat this is what was
confusing people think the laser oh
we're gonna get it to 100 million
degrees in fact you want the exact
opposite of this what you want to do is
get essentially a rocket going out like
this and then what happens is that the
sphere like and this is happening in a
billionth of a second or less actually
this rapidly that that Force like so
rapidly compresses the fuel that what
happens is that you're squeezing down on
it and and and you know it's like what
was the CBB that's bad actually B I
should have started with a basketball
basket goes from like a basketball down
to something like like this and then
billionth of a second
and when that when that happens I mean
you scale that in your mind so when that
happens and in this this comes from
almost from classical physics so there's
some Quantum in it as well too but
basically if you can do this
um like very uniformly and so-called
adiabatically like you're not actually
heating the fuel what happens is you get
adiabatic compression such that the very
center of this thing all of a sudden
just spikes up in temperature because
it's it's it's actually done so fast so
why is it called inertial Fusion it's
because you're doing this on such fast
time scales that the inertia of the hot
fuel basically is still finite so it
can't like push itself apart before the
fusion happens
oh wow so how do you make it so how do
you make it so fast this is why you use
lasers because you're applying this
energy in very very short periods of
time like under a fraction of a
billionth of a second and so basically
that and then the force which is coming
from this comes from the energy of the
lasers which which is basically the
rocket action which does the compression
which is the force is the inward facing
Force is is that is that increasing the
temperature no exponential you want to
keep the fuel cold
and then and just literally just ideally
compress it and then in something which
is at the very center of that compressed
sphere because you've compressed it so
rapidly the laws of physics basically
require for it to increase in
temperature so the the effect is like if
you know the thing so adiabatic cooling
were actually fairly familiar with if
you take a spray can right and you push
the button when it when it rapidly
expands it cools this is the nature of a
lot of cooling technology we use
actually well the opposite is true that
if you would take all of those particles
and jam them together very fast back in
they want to heat up
and that's what happens and then what
happens is you you basically have this
very cold compressed set of Fusion fuel
and at the center of this it goes to
this 100 million degrees Celsius and so
if it gets to that 100 million degrees
Celsius the Fusion fuel starts to burn
and when that Fusion fuel starts to burn
it wants to heat up the other cold fuel
around it and it just basically
propagates out so fast that what you
would do ideally you would actually burn
in a fusion sense most of the fuel
that's in the pellet so this was very
exciting because what they had done was
they it's clear that they propagated
this they got this what they call a hot
spot and in fact that this heating can
propagate it out into the fuel
um and that's that's the science behind
inertial Fusion so the idea behind a
reactor is based on this kind of
inertial uh uh confinement is that you
would what have a new BB every like 10
times a second or something like and
then there's some kind of yeah so
there's a incredible device that you
kind of implied that kind of has to
create one of those BBS that did so you
have to make the BBS very fast there's
reports on this but about what what does
it mean you know the starting point is
can you make this game
so this was a scientific achievement
primarily because and the rest is just
engineering no no no the rest is
incredibly complicated engineering well
in fact there's still physics hurdles to
overcome so so where does this come from
and it's actually because if you want to
make an energy source out of this
um this had a gain of around 1.5 that
namely the Fusion Energy was
approximately was 1.5 times the the
laser input energy okay this is a fairly
significant threshold however from the
from the science of what I just told you
is that there's two fundamental
efficiencies which come into it which
really come from physics really one of
them is hydrodynamic efficiency what I
mean by this is that it's a rocket so
this just has a fundamental
uh efficiency built into it which comes
out to orders of like 10 percent so this
means is that your your ability to do
work on the system is just limited by
that okay and then the other one is the
efficiency of laser systems themselves
which if they're wall plug efficiency is
10 you've done spectacularly well in
fact the wall plug efficiency of the
ones using experiments are like more
like one percent right so when you go
through all of this the approximate you
know place that you're ordering this is
for for fusion power plant would be a
gain of a hundred not 1.5 so you still
you know and hopefully we see
experiments that keep climbing up
towards higher and higher gain but then
the whole fusion power plant is a
totally different thing so it's not one
it's not one BB and one laser pulse per
day it's like ten times five or ten
times per second like
that right so you're doing it there and
then then and then comes the other
aspects so it's making the targets
delivering them being able to repeatedly
get them to burn and then we haven't
even talked about like how do you then
get the Fusion Energy out which is
mainly because these things are
basically micro you know implosions
which are occurring so this energy is
coming out to some medium on the outside
that you've got to figure out how to
extract the energy out of this thing how
do you convert that energy to
electricity so in the end you have to
basically convert it into heat in some
way so most of the pro what you in the
end what Fusion makes mostly is like
very energetic particles from the fusion
reaction so you have to slow those down
in some way and then make heat out of it
so basically the conversion of the
kinetic energy of the particles into
heating some engineered material that's
on the outside of this and that's from a
physics perspective is a somewhat solved
problem but from an engineering is is
still it's still yeah physics I can draw
the I can show you all the equations
that tell you about how it slows down
and converts kinetic energy into heat
and then what that heat means you know
you can write out like an ideal thermal
cycle like a carnosis so the physics of
that yeah great the integrated
engineering of this is a whole other
thing a last case of maybe talk about
the difference between a natural
magnetic uh but first we'll talk about
magnetic but let me just Linger on this
breakthrough you know it's nice to have
exciting things but
in a deep human sense there's no
competition in science and engineering
well like you said we were broad first
of all we are a Humanity all together
and you talk about this it's a bunch of
countries collaborating it's it's really
exciting uh there's a nuclear fusion
Community broadly but then there's also
MIT there's colors and logos and it's
exciting and there's a that you uh you
have uh friends and colleagues here that
that work extremely hard and done some
incredible stuff is there some sort of
how do you feel seeing somebody else uh
get a breakthrough and uh using a
different technology is that exciting uh
is this does the competitive fire uh get
uh all of the above I mean I mean the
ignition you know I have so uh you know
to you know just to wave the wave the
flag a little bit so MIT was a central
player in in this in this accomplishment
um interesting I would say it showed our
two some of our two best traits so one
of them was that the
like how do you know that this happened
this measurement right so one of the
ways to do this is if I told you is that
the in the DT Fusion what it actually
the product that comes out is helium I
would call an alpha but it's helium
um and a free Neutron right so the
neutron contains 80 percent of the
fusion of the energy released by the
fusion reaction and it also because it
has lack it lacks a charge it basically
tends to just escape and go flying out
so this is what we would use eventually
for
that's mostly what Fusion Energy would
be but so what um my my colleagues my
scientific colleagues at uh at the plaza
science Infusion Center built were
extraordinary measurement tools of being
able to see the exact details of not
only the number of neutrons that were
coming out but actually what energy that
they're at and by looking at that that
configuration it reveals enormous I'm
not gonna I'm not gonna scoop them
because they need to publish the paper
but it it reveals enormous amounts of
scientific information about what's
happening in that process that I just
described so exciting I mean and I there
you know I have colleagues there that
have worked like for 30 years on this
for that moment of course you're excited
for them I mean and there's one of those
like there's there's nothing it's hard
to describe to people who aren't they
haven't it's like almost addicting to be
a scientist when you get to be at the
Forefront of research of anything like
when you see like an actual discovery of
some kind and you're looking at it
particularly when you're are the person
who did it right and you go no human
being has ever seen this or understood
this it's like it's pretty thrilling
right so even even in proxy it's it's
incredibly thrilling to see this it's
not I don't know it's rivalry or
jealousy it's like I can tell you
already Fusion is really hard so
anything that keeps pushing the needle
forward is a good thing but we also have
to be realistic about what it means you
know to making a Fusion Energy System
that's that's and then but that's the
fun I mean these are the are still the
early steps you maybe you can say the
early leaps uh
so let's talk about the magnetic
confinement uh what is how does uh
magnetic confinement work what's the
takamak uh yeah how does it all work so
go back to that so why inertial
confinement works on the same principle
that a star works so like what is the
confinement mechanism in the star is
gravity
because it's it's it's it's its own
inertia of the something the size of the
sun basically pushes a literally a force
by gravity against the center so the
center is is very very hot 20 million
degrees and literally outside the sun
it's essentially zero because it's
vacuum of space how the hell does that
do that it does that by and is out of
through like why doesn't just leak all
of its heat it doesn't leak its heat
because it all held together by the fact
that it can't escape because of its own
gravity so this is why the fusion
happens in the center of the Tsar like
we think of the surface of the Sun as
being hot that's the coldest part of the
star so if our own sudden this is about
in 5500 degrees a beautiful Symmetry by
the way it's like so how do we know all
this because we can't of course see
directly into the interior of the Sun by
knowing the volume and the temperature
of the surface of the Sun you know
exactly how much power it's putting out
and by this you you know that this is
coming from Fusion reactions occurring
at exactly the same rate in the middle
of the Sun
is it possible as a small tangent to
build uh an inertial confinement system
like the sun is it possible to create a
sun it is of course possible to make a
sun although he's even have stars but it
is not impossible on Earth because for
the simple reason that it takes the
gravitational force is extremely weak
and so it takes something like the size
of a star to make fusion occur in the
center well I I didn't mean on Earth I
mean if you had to build like a second
sun how did you do it you can't there's
not enough hydrogen around yeah so the
the limiting factor is the the just the
hydrogen yeah I mean the the forces that
an energy that it takes to assemble that
is just mind-boggling all right so we
would do that to be continued yeah to be
continuous so what are we doing it with
so in the one that I just described it's
like you say so you have to replace this
with some Force which is better than
that and so what I'd mean by is it's
it's stronger than that so when I talked
about the laser Fusion this is coming
from the force which is enormous
compared to gravity like like from the
rocket action of pushing it together
so in magnetic confinement
we use another force of nature which is
the electromagnetic force and that's
very it's orders and Orders of magnitude
stronger than the gravitational force
and the key force that matters here is
that if you have a Charged particle that
namely it's a particle that has an
electric net electric charge and it's in
the proximity of a magnetic field then
there is a force which is exerted on
that particle
so this is called the Lowrance Force for
those who are keeping track so that is
the force that we use to replace
physical containment
so and so this again confuses how do you
hold something at 100 million degrees
it's impossible in a physical container
this is not like you know it's not this
plastic bottle holding in this liquid or
a gas chamber what you're doing is
they're using and you're immersing the
fuel in a magnetic field that it
basically exerts a force at a distance
this comes back again to again like why
plazas are so strange it's the same
thing here and if it's immersed in this
magnetic field you're not actually
physically touching it but you're making
a force go onto it so that's the and
that's the inherent feature of of
magnetic confinement and then magnetic
confinement devices are like a Toca Mac
are basically uh configurations which
exploit the features of that magnetic
containment there's several features to
it one is that the stronger the strength
of the magnetic field the stronger the
force
and for this reason is that if you
increase the strength of magnetic fields
this means that the containment because
namely the force which you're pushing
against it is more effective
and the other feature is that there is
no Force so for those magnetic fields
what are these things they're also
invisible but you know if you think of a
permanent magnets or your fridge magnet
there are there are field lines which we
actually designate as arrows which are
going around you sometimes see this in
school when you have the you know the
iron filings on a thing and you see the
directions of the magnetic field lines
or or when you use a compass right so
that's telling you nor because we're
living in an immersed magnetic field
made by the Earth which is at very low
intensity magnetic but it's strong
enough we can actually see what
direction is so this is the arrow that
the magnetic field is pointing it's
always pointing North and for us is that
so an interesting feature of this force
is that there is no Force along the
direction of the magnetic field there's
only force in the directions orthogonal
to the magnetic field so this by the way
is a huge deal in in in in in in a whole
other discipline of plasma physics which
is like that the study of like our near
atmosphere so the study of aurora
borealis what's happening in the near
atmosphere what happens when solar
flares hit the magnetic in fact
remember I said Fusion is the reason
that life is responsible
in the universe where you could also
argue so is magnetic confinement because
the the charged particles which are
being emitted from from the Galaxy and
from our own star would be very very
damaging to on Earth so we get two
layers of protection one is the
atmosphere itself but the other one is
the magnetic field which surrounds the
Earth and basically traps these charged
particles so they can't get away it's
the same it's the same it's the same
deal how do you create a strong magnetic
field yeah so with a giant magnet giant
magnet yeah so it's it's basically true
engineering there's essentially there's
essentially two ways to create a magnet
so one of them is that we're familiar
with like fridge magnets and so forth
these are so-called permanent magnets
and what it means is that Within These
the atoms arranged in a particular way
that it produces the electrons basically
arranged in a particular way that it
produces a permanent magnetic field that
is set by the material so those 10 those
have a fundamental limitation how strong
they can be and they also tend to have
this like circular shape like this so we
don't use we don't typically use those
so what we use are so-called
electromagnets and what is this it's
like um so the other way to make a
magnetic field also go back to your you
know your your Elementary School physics
uh or science class is that you take a a
nail and you wrap a copper wire around
it and connect it to a battery then it
can pick up iron filings this is an
electromagnet
at its simplest what it is it's an
electric current which is going in a
pattern around and around and around and
what this does is it produces a magnetic
field which goes through it by the laws
of electromagnetism
so that's what an electro that's so
that's how we make the magnetic field in
these in in these configurations and the
key there is that you it's not limited
by the magnetic property of the material
the magnetic field uh amplitude is set
by the amount of the the geometry of
this thing and the amount of electric
current that you're putting through and
the more electric current that you put
through the more magnetic field that you
get the closest one that people maybe
see is one of my one of my favorite
skits actually was Super Dave Osborne on
YouTube it's probably probably past
years again a show called bizarre Super
Dave Osborne which is a great comedian
cult he was a stunt man and one of his
tricks was that he was he gets into a
car and then one of those things in the
junkyard comes down you know and picks
up the car and then puts it into the
into the crusher this is his stunt which
is pretty hilarious anyway
um but that thing that picks him up like
how does that work that's actually not a
permanent magnet it's a it's an
electromagnet and so you can turn by
turning off and on the power supply it
turns off and on the magnetic field so
this means you can pick it up and then
when you switch it off the magnetic
field goes away and the car drops okay
so that's that's what it looks like
speaking of giant magnets MIT and
Commonwealth Fusion systems CFS built a
very large high temperature
superconducting electromagnet that was
ramped up to a field strength of 20
Tesla the most powerful magnetic fields
of its kind ever created down Earth
because I enjoy this kind of thing can
you please tell me about this magnet
yeah sure oh it was it's fun yeah
there's a lot to parse there so maybe uh
we so we already explained an
electromagnet which
in general is what you do is you take
electric current and you force it to to
follow a pattern of some kind typically
like a circular pattern around and
around and around around it goes the
more time the more current and the more
times it goes around the stronger the
magnetic field that you make okay
and as I pointed out it's like really
important in magnetic confinement
because it is the the force that's
produced by that magnet in fact
technically it goes like the magnetic
field squared because it's it's a
pressure which is actually being exerted
on the plasma to keep it contained uh
just just so we know for a magnetic
confinement what is usually the geometry
of the magnet what are we the geometry
yeah so the geometry is typically that
typically is what you do is you want to
produce a magnetic field that Loops back
on itself and the reason for this was
goes down to the nature of the force
that I described
which is that there's no there's no
containment or Force along the direction
of the magnetic field so here's a
magnetic field in fact what what it's
more technically or more graphically
what it's doing is that when the when
the plasma is here's plasma particles
here there's a magnetic field what it
does is it forces all those because of
this this Lorenz force it makes all of
those charged particles execute circular
orbits around the magnetic field and
they go around like this but they stream
freely along the magnetic field line so
this is why the nature of the
containment is that if you can get that
Circle smaller and smaller it stays
further away from Earth temperature
materials that's why the confinement
gets better but the problem is is that
because it free streams along so we just
have a long straight magnetic field okay
it'll just keep leaking out the ends
like really fast so you get rid of the
ends so you basically Loop it back
around so what these look like are
typically donut shaped or more
technically toroidal shape but donut
shaped um things where this collection
of magnetic fields Loops back on itself
and it also for reasons which are more
complicated to explain basically it also
twists it also twists slowly around in
this direction as well too so that's
what it looks like that's what the
plasma looks like because that's what
the fuel looks like so then this means
is that the um the electromagnets are
configured in such a way that it
produces the desired magnetic fields
around this so they precise does this
have to be you were probably listening
to our conversation with some of my
colleagues yesterday so it's actually
it's it depends on the configuration uh
about how you're doing it the
configuration of the plasma the
configuration of the electromagnets and
about how you're achieving this this
requirement
um it it's it's fairly precise but it
doesn't have to be in particularly in
something like a Tokamak what we do is
we produce planar coils that just mean
they're flat and we situate them so if
you think of a circle like this what
does it produce if you put current
through it it produces a magnetic field
which goes through the circle like this
so if you align many of them like this
this this this this there's things
online you can go see the picture to to
you keep arranging these around in a
circle itself this forces the magnetic
field lines to basically just keep
executing around like this so you tend
to align that one tends to re well it
requires good confine or good alignment
it's not like in insane alignment
because you're you're actually
exploiting the symmetry of the situation
to to help it there's another kind of
configuration of magnetic of this kind
of magnetic confinement called a
stellarator which is we have these names
from for historic reasons which is
different than a Taco Mac it's different
than a token that actually works on the
same physical principle that namely in
the end it produces a plasma which Loops
in magnetic fields which loop back on
themselves as well but in that in that
case the totality basically the totality
of the confining magnetic field is
produced by external three-dimensional
magnets so they're Twisted
um and it turns out the Precision of
those is is more stringent yeah so are
taco Mac's by far more popular for
research and development currently than
Stellar Raiders of the concepts which
are there of the token Mac is by far the
most mature in terms of its breadth of
performance and
um and thinking about how it would be
applied in a Fusion Energy System in the
history of this was that many in fact
you asked about if we go back to the
history of the Plato science infusion
center the history of fusion is that
people
scientists had started to work on this
in the 1950s it was all hush-hush and
you know Cold War and all that kind of
stuff and and it's like they realized
holy cow they're like this is like
really hard like we actually don't
really know like what we're doing in
this because everything was at low
temperatures they couldn't get
confinement it was interesting and then
the the they Declassified it and this is
one of the few places that the the west
and the Soviet Union actually
collaborated on was a science even
during the Cold War even during the
middle of the Cold War it was really and
this actually perpetuates all the way
till now for we we can talk about the
the project that that is sort of
captured in now
um
uh but and and the reason they
Declassified it is because like
everything like kind of like sucked
basically you know about trying to make
this confinement in high temperature
plasma and then the Russians then the
Soviets right came along with this
device called the Tokamak which is a
Russian acronym which basically means
uh magnetic coils arranged in the shape
of a donut and
and um they said holy holy cow like
everyone was stuck at like a meager like
half a million degrees or half a million
degrees which is like in Fusion terms of
zero basically
um and then they come along they say oh
we've actually achieved a temperature 20
times higher than everybody else and
it's actually started to make fusion
reactions and everyone just go oh you
know no way it's just hype from this
it's like there's no way because we
failed at this
um it's a great story in the history of
fusion is that then but this insisters
said no look you can see this from our
data it's like this thing is really hot
and it seems to be working this is you
know late 1960s and there was a uh there
was a team that went from the United
Kingdom's Fusion development lab and
they brought this very fancy amazing new
technology called a laser
and they use this laser and they shot
the laser beam like through the plasma
and by looking at the scattered light
that came from the they go that
basically the scattered light gets more
broadened in its Spectrum if it gets
hotter so you could you could exactly
tell the temperature of this and even
though you're not physically touching
the plasma it's like holy cow you're
right it is like it is 10 million
degrees and so this was one of those
explosions of like everyone in the world
then wanted to build a token back
because it was clearly like wow this is
like so far ahead of everything else
that we tried before
um so that actually has a part of the
the story to MIT in the Plato science
infusion center was
why is there a strong Fusion in a major
Fusion program at MIT it was because we
were host to the Francis bitter magnet
laboratory which is also the National
High field magnet laboratory well you
can see where this goes right from this
you know we're kind of telling the
stories backwards almost but you know
the the the Advent of a Toca Mac along
with the fact that you could makes very
strong magnetic fields with the
technology that had been developed at
that laboratory that was the origins of
sort of pushing together the physics of
the of the plasma containment and the
magnet technology and put them together
in a way that I would say is you know a
very typical MIT success story right we
don't do just just pure science or pure
technology we sort of set up this
intersection between them and there were
several Pioneers that of of my of the of
people at MIT like Bruno copy who's a
professor in the physics department and
Ron Parker who was a professor in
electrical engineering and nuclear
engineering it's like even the makeup of
the people right has got this blends of
Science and Engineering in them and
that's actually was the origin of the
Plato science infusion center was was
doing those things so anyway so back to
this so why so yes tokamax have been
have achieved the highest in magnetic
Fusion by far like the the the best
amounts of these of these conditions
that I had talked about and in fact
pushed right up to the point where they
were near QP of one they just didn't
quite get over one so can we actually
just Linger on the uh on the
collaboration across different nations
just um yeah maybe looking at the
philosophical aspect of this
even in the Cold War
there's something hopeful to me besides
the energy that these giant
International projects
are a really powerful way to ease some
of the geopolitical tension even
military conflict across Nations there's
a
war in Ukraine
and Russia
there's a brewing tension and conflict
with China just the world is still
um seeking military conflict cold or hot
what can you say about sort of the
lessons of the 20th century and these
giant projects uh in their ability to
ease some of this tension
so it's it's a great question so as I
said there was a reason because it was
so hard that was one of the reasons they
they Declassified it um and actually
they started working together in some
sense on it as well too and I think it
was really there was
you know and are you ristic or or
altruistic
um aspect to this it's like this is
something that could change you know the
future of humanity and its nature and
its relationship with energy isn't this
something that we should work on
together right and and and that went
along in those ones and in particularly
that any kind of place where you can
actually have an open exchange of of of
people who are sort of at the
intellectual frontiers of your Society
this is a good thing right of being able
to collaborate I've I've had the I mean
I've had have had an amazing you know
career I've worked with people from it's
like hard to throw a dart at a country
and on the map and not hit a country of
people that I've been able to work with
how amazing is that and and even just
getting small numbers of people to
bridge the cultural and societal
societal uh um you know divides is a
very important thing even when it's a
very teeny action of the overall
populations it can be held up as as an
example of that but it's interesting
that if you look at then that continued
collaboration which continues to this
day is that it was it this actually
played a major role in fact in East-West
relations or like so Soviet West
relations Is that um back in the uh the
Reagan Gorbachev days which of course
were interesting in themselves of all
kinds of changes happening you know on
both sides right
um and but still like a desire to you
know push down the stockpile of nuclear
weapons and all that within that context
there was
um a very fairly significant historic
event that at one of the the Reagan
Gorbachev Summits is that they had
really they didn't get there like they
couldn't figure out how to bargain to
the point of the of the some some part
of the tree dick anymore the details of
it anymore
but they needed some kind of a symbol
almost to say but we're still going to
keep working you know towards something
that's important for all of us whether
they pick a fusion project
and that was in the mid-1980s and
actually then after so they basically
signed an agreement that they would move
forward to like literally collaborate on
on a project whose idea would be to show
large net energy gain infusions
commercial viability and work together
on that and very soon after that Japan
joined as did the European Union and now
um that project it evolved over a long
period of time and had some interesting
political ramifications to it but in the
end this actually also had South Korea
India and China join as well too so
you're talking about make major
a major fraction of and now Russian of
course instead of the Soviet Union
um and actually that Coalition is
holding together despite the obvious
political you know uh turmoil that's
going around on all those things and
that's a project called eter which is in
under construction in the south of
France right now can you actually before
we return to the giant magnet and maybe
even talk about spark and this stuff
going to all amazing stuff going on at
MIT what is theater what what is this
International nuclear fusion Mega
project uh being built in this in the
south of France so it's scientific
purpose is a worthy one then it's
essentially an any Fusion device
the thing that you want to see is more
and more relative amounts of
self-heating and this is something that
had not been seen although although we
have made Fusion reactions and we'd seen
small amounts of the self-heating we
never got to a dominant this actually
goes to this QP business okay the goal
of eater and it shifted around a little
bit historically but very you know
fairly quickly became we want to get to
a large amount of self-heating so this
is why it has a its primary feature is
to get 2qp of around 10 and through this
this is a way to study this plasma that
has more higher levels of
self-determination around on it
but it also has another feature which
was let's produce fusion power at a you
know relevant scale
and and actually they're linked together
which actually makes sense you think
about it is that because the fusion
power is the heating Source itself this
means that they're linked together and
so either makes it is projected to make
about 500 million watts of fusion power
so this is a significant amount like
this is what you would use
you know for powering cities so it's not
just the research that really it is the
development of really trying to achieve
scale here so self-heating and scale
yeah yes so this this meant then too is
the the development of an industrial
base that can actually produce the
Technologies like the electromagnets and
so forth and to do it with it is a
Tokamak it is it is one of these yes but
very interesting it also revealed
limitations of of this as well too well
it is it's interesting is that it is
clearly a
um on paper and in fact in in practice
as well too the world the world you know
and very different political systems and
you caught you consider at least
geopolitical or economic rivals or
whatever you want to use like working
towards a common cause and one that we
all think is Worthy is is very like okay
that's very satisfying but it's also
interesting to see the limitations of
this it's because well you've got seven
you know chefs in the kitchen
so what is this what does this meant in
terms of the speed of the project and
the ability to to govern it and so forth
it's just been a challenge uh honestly
around this and this is I mean it's very
hard technically what's what's occurring
but when you also introduce such levels
of I mean this isn't just me saying it
there's like GAO reports from the US
government and so on this is It's hard
to like steer all of this around
um and what that's tended to do is make
it it's it's not the fastest decision
making process you know my own personal
view of it was it was it was interesting
because you asked me you said about the
magnet and Commonwealth Fusion systems
it was I worked most of my career on
eater because when I came into the field
in the early 1990s when I completed my
PhD and started to work this was one of
the most like you can't imagine being
more excited about something like we're
going to change the world with this
project we're going to do these things
and we just like Port like an entire
generation and afterwards as well too is
just poured their imagination and their
creativity about making this thing work
very good but at also at some point
though when you know when it got to
being another five years of delay or a
decade of delay you start asking
yourself well is this what I want to do
right am I going to wait for for this so
it was a part of me starting to ask
questions with my students I was like
is there another way that we can get to
this extremely worthwhile goal that
maybe maybe it's not that that maybe
it's not that pathway and the other part
that was clearly frustrating to me
because I I'm an advocate of fusion you
asked me about was I you know I was like
well it's laser Fusion or inertia or
inertial Fusion or magnetic Fusion I
just want Fusion Energy okay because I
think it's so important to the world is
that but the other thing if that's the
case
then why do we have only one attempt at
it on the entire planet which was either
it's like that makes no sense to me
right we should have multiple attempts
at this with different levels of
whatever you want to think about a
technical schedule scientific risk which
are Incorporated in them and that's
going to give us a better chance of
actually getting to the goal line with
that Spirit your leading mit's effort to
design spark a compact High field DT
burning takamak
how does it work what is it what's the
motivation uh what's the design what are
the ideas behind it yeah at its heart
it's exactly the same concept as eater
this is basically a configuration of
electromagnets it's arranged in the
shape of a donut and within that we will
do we would do the same thing that
happens in all the other token Max and
including an eater and in this one is
that namely you put in gas make it into
a plasma you heat it up it gets about
100 million degrees
the differentiator in spark is that we
use the actual deuterium tritium Fuel
and because of the access to very high
magnetic fields it's in a very compact
space it's very very small
what I mean by small so it's 40 times
smaller in volume than either but it
uses exactly the same physical
principles so this comes from the high
magnetic field so in the end like what
is why does this matter what it does is
it does those things and it should get
to the point where it's producing over
100 million watts of fusion power
but remember it's 40 times smaller so
either was 500 megawatts technically our
design is around 150 megawatts so it's
only about a factor of three difference
despite being 40 times smaller
um and we see
um QP large
order of 10 or something like this at
that at that at that state is very
important scientifically because this is
basically matches what eater is looking
to do the plasma is dominated by its own
heating that's very very important and
it does that for about 10 seconds
and the reason it's for 10 seconds is
that in terms of that that basically
allows everything to settle in terms of
the fusion in the plasma equilibrium
everything is nice and settled so you
know you have seen the physical state at
which you would expect a power plant to
operate basically for for magnetic
Fusion like wow right
but it's more than that and it's more
than that it's because about who's
building it and why and how it's being
financed
um so that scientific pathway was made
possible by the fact that we had access
to a next generation of magnet
technology so to explain this real quick
why do we call it you you said it in the
words a superconducting magnet what does
this mean
superconducting magnet means that the
materials which are in the electromagnet
have no electrical resistance therefore
when the electric current is put into it
the current goes around unimpeded so it
could basically keep going around and
around you know technically for infinity
and what that means are for eternity and
what that means is that the um when you
energize these large electromagnets
they're they're using basically zero
electrical power to maintain them
whereas if you would do this in a normal
wire like copper you basically make an
enormous toaster oven that's consuming
enormous amounts of power and getting
hot which is the problem that was the
technical breakthrough that was realized
by myself and at the time my students
and postdocs and colleagues at MIT was
that we we saw the Advent of this new
this new superconducting material which
would allow us to access much higher
magnetic fields is basically the next
generation of the technology and
um and it was quite disruptive diffusion
that namely what it would allow that if
we could if we could get to this point
where we can make the round 20 Tesla We
Knew by the rules of tokamax that this
was going to be is going to allow us to
vastly shrink like the sizes of these
devices so it wouldn't take
um although although it's a worthy goal
it wouldn't take a seven nation
International you know treaty basically
to build it you could build it with a
company and a university it's the same
kind of design but now using the
superconducting magnets yeah and if in
fact if you look at it's like it's if
you just expand the size of it they're
like they look almost identical to each
other because it's based on the and
actually that comes for a Reason by the
way is that it also looks like a bigger
version of the Toca Mac that we ran at
MIT for 20 years where we established
the scientific benefits in fact of these
higher magnetic fields so that's the
pathway that runs so always say so what
does this mean the context is different
because
it was made because it's primarily being
made by a a private sector company spun
out of MIT because the way that it
raised money and the purpose of the
entity which is there is to make
commercial fusion power plants not just
to make a scientific experiment this is
actually why we have
um
that's why we have a partnership right
is that our purpose at MIT is not to
commercialize directly but boy do we
want to advance the technology and the
science that comes along this and that's
the reason we're sort of doing it
together so it's MIT and Commonwealth
Fusion systems so what's what's
interesting to say about financing and
this seems like from a scientific
perspective maybe not an interesting
topic but it's perhaps an extremely
interesting topic I mean you can just
look at the testing between SpaceX and
NASA for example yes it's just clear
that there's different financing
mechanisms can actually significantly
accelerate
the development of Science and
Engineering
it's great that you brought that up we
use several historic analogs and one of
them is around SpaceX which is an
appropriate one because space you know
putting things into orbit has a just a
has a minimum size to it and integrated
technological complexity and budget and
things like this so you know our point
when we were like talking about starting
like a fusion commercialization you know
company people look at you like like
isn't this still really just a science
experiment you know but are one of the
things that we pointed to was SpaceX to
say well tell me like 25 years ago how
many people would have voted that you
know the the leading entity on the
planet to put things into orbit it's a
private company people would have
thought you were not so right it's like
and what is interesting about SpaceX was
that it proved it's more than actually
just financing
it's really the purpose of the
organization so the purpose of a gun and
I'm not against Public Finance or
anything like that but the purpose of a
public entity like in like NASA
correctly you know speaks to the
political
because because the cost comes from the
political you know uh assembly that is
there and and I guess from us eventually
as well too but its purpose wasn't about
like making a commercial product it's
about fundamental Discovery and so forth
which is all which is all really great
it's like why did why did SpaceX it's
interesting because why did SpaceX
succeed so well is because the idea was
it's like the the focus that comes in
the idea that you're going to
relentlessly like reduce cost and
increase efficiency is a drive that
comes from the commercial aspect of it
right and this also then changes
um the people in the teams which are
doing it as well too and in fact
trickles throughout the whole thing
because the purpose isn't while you're
while you're advancing things like it's
really good that we can put things in
orbit a lot less more cheaply like in
advance of science which is an
interesting Synergy right and it's the
same thing that that we think is going
to happen in fuse that namely these this
is a bootstrap effect that actually that
when you start to push yourself to think
about near-term commercialization it
like allows the size to get in hand
faster which then allows the
commercialization to go faster into an
up we go by the way we've seen this also
in another like again it's a you have to
watch out with with analogies because
they only can go so far but like biotech
is another one like you look at the
Human Genome Project which was
it's sort of like it's it to me that's
like like mapping the human genome is
like like that we can make net energy
from Fusion like it's one of those like
in your drawer that you go this is a
significant achievement by Humanity
right in the century and there's the
Human Genome Project fully government
funded it's going to take 20 25 years
because we basically know the technology
we're just going to be really diligent
keep going and then all of a sudden what
comes along disruptive technology right
you can sequence you you know shotgun
sequencing and computer you know
recognition patterns and basically oh I
can do this a hundred times faster
like wow right and so so that's really
the uh you know to me that the story
about why we started why we launched
Commonwealth Fusion systems was more
than just about another source of
funding which is a different source of
fun because it comes it's also a
different purpose which is very
important but there's also something
about a mechanism that creates culture
so giving power to like a young student
ambitious student to have a tremendous
impact on the progress of nuclear fusion
creates a culture that actually makes
progress more aggressively like like you
said when Seven Nations collaborate it
gives more incentive to the bureaucracy
to slow things down to kind of have
let's have first have a discussion and
certainly don't give voice to the young
ambitious Minds that are really pushing
stuff forward yeah and there's something
about like the private sector that
rewards encourages inspires young minds
to say in the most beautiful ways Fu to
the
just for the boss yeah just to like
we'll make it faster we'll make it
simpler we'll make it better we'll make
it cheaper yeah and sometimes that
brashness doesn't bear out you know
that's an aspect that you just take a
different risk profile as well too but
you're right it's this you know of them
I mean it was interesting our our own
trajectory at the at the fusion Center
was like we were pushed into this place
by necessity as well too because I told
you we have and we had operated for a
long time a Tokamak at uh on the MIT
campus achieve these World Records like
100 million degree plasma and so I was
like wow this is fantastic but
you know somewhat ironically I have to
say is that it was like oh but we're not
this isn't the future of fusion anymore
like we're not we're just gonna stop
with small projects because it's too
small right so we should need we need to
really move on to these much bigger
projects because that's really the
future of fusion and so it was defunded
um and this basically put at risk like
like we were going to essentially lose
MIT in the ecosystem really a fusion
both from the research but also clearly
important from the educational part of
it so we you know we push back against
this we got a Lifeline we were able to
go it was in this it was in this time
scale that we basically came up with
this idea it's like we should do this
and in the end it was all of those the
the people who were in the sea level of
the company were all literally students
who got caught in that they were PhD
students at the time so you talk about
enabling another generation it's like
yeah there you go right so spark gave a
lifeline
but it's way more than that it was it
wasn't just about like surviving for the
sake of surviving it was like in the end
for me it became like this I remember
the moment when you talk about these
moments as a scientist and we were just
like we were working so hard about
figuring out like does this really would
this really work like in this it's
complex like does the magnet work does
the interaction with the plasma work
does all these things work and it was
just a grind push push push push and I
remember the moment because I was
sitting
in my office in Brookline and and and
and there was just like I read like and
I was in I don't know whatever the 20 or
40th slide or something into it and it
was sort of that moment like it just
came together and I like I I got I
couldn't even sit down because all I was
just like my wife was like why are you
walking around the apartment like this
like I just couldn't she I said it's
going to work like it's going to work
like holy that moment of realization is
like kind of amazing but it also brings
the responsibility of making it work as
well so you mean like that magic
realization that you could have this uh
this modern uh Magnum technology and you
can actually like why do we need to work
with either we can do it here yeah yeah
but it's interesting that eater is
um that one one of one of the reasons
that like that we started with a group
of six of us at MIT and then it's once
we got some funding through the through
the establishment of the company it
became a slightly larger but in the end
we had a rather small team like this was
like a a team of order of like 20 to 25
people design spark and like a like
about two years right how does that
happen well we're clever but you have to
give eater it's due here as well too
that again this is an aspect always of
the bootstrap up like I go back to the
Human Genome Project so modern day
genomics would not be possible without
the underlying basis that came from
setting that up it had to be there it
had to be curiosity driven public
program is the same with either but we
because we had the tools that were there
to understand either we also have the
tools to understand spark so we we
parlayed those in an extremely powerful
way to be able to tell us about what was
going to happen so these things are
never simple right it's like people look
at this go oh this means we should like
should we really have a public-based
program about Fusion or should we have
it all in the private it's like no no
the answer is neither way because in all
these complex Technologies you have to
keep pushing on all the fronts to
actually get it there
so you know the natural question when
people hear breakthrough with the with
the inertial confinement with the
magnetic confinement is so when will we
have commercial yeah
um reactors power plants that are
actually producing electricity what's
your sense
um
looking out into the future when do you
think you can Envision a future what we
have actual electricity coming from
nuclear fusion partly driven by us but
in other places as well too so there's
the Advent what's you know what's so
different now than three or four years
ago like we launched around four years
ago what's so different now is is the
Advent of a very nascent but seemingly
robust like commercial Fusion you know
Endeavor so it's not just Commonwealth
Fusion systems there's something like 20
plus you know companies there's a sector
now there's a sector they actually they
actually have something called the
fusion industry Association which if
your viewers want to go see this this
describes the difference and they've got
this plethora of approaches like I
haven't even described all the
approaches I've basically described the
mainline approaches
um you know and they're all at varying
degrees of Technical and scientific
maturity with very huge different you
know balances between them but what they
share
is that because they're going out and
finding getting funding from the private
sector is that their stated goals are
about
getting fusion into place so that both
it meets the investors demands which are
interesting right in the time skills of
that but also it's like well there's
going to and why it's because it's easy
there's gonna there's this enormous push
driver about getting carbon-free energy
sources out into the market and whoever
figures those out is going to be both
very it's going to be very important
geopolitically but also economically as
well too so it's a different kind of
a bat I guess or a different kind of
gamble that you're taking with Fusion
but it's so disruptive that it's like
there's there's a essentially a class of
investors and teams that are ready to go
after it as well too so what do they
share in this they typically share
um getting after Fusion on a time scale
so that could it have any relevance
towards climate change baling climate
change and I would say this is difficult
but it's it's fairly easy because it's
math so what you do is you actually go
to some Target like 20 50 or 2060
something like this and say I want to be
blank percent of the the world's market
of electricity or something like that
and you and we know historically what it
takes to evolve and distribute these
kinds of Technologies because every
technology takes some period of time
so-called s-curve it's basically
everything follows a logarithmic
exponential type curve it's a straight
line a log plot and um like you look at
winds solar fission they all follow the
same thing so it's easy you take that
curve and you go that slope and you work
backwards and you go if you don't start
in the early 2030s like
it's not going to have uh you know it's
not going to have a significant impact
by that time so all of them share this
idea and in fact it's not just the
companies now the U.S federal government
has a program that was started last year
that said we should be looking to try to
get like the first and what I mean by
like what does it mean to start that
you've got something that's putting
electricity on the grid a pilot what we
call it and if that can get started like
in the early 2030s you know the idea of
ramping it up you know makes sense
that's math right so that's the ambition
then the question is and and actually
this is different because the government
program and that they vary around in
this so for for example the United
Kingdom's government idea was to get the
first one on by 2040.
and China has Ambitions probably middle
2030s uh or maybe a little bit later and
Europe uh you know Continental Europe is
it's a little bit I'm not exactly sure
where it is but it's like later it's
like 2050 or 2060 because it's mostly
linked to the eater timeline as well too
um the fusion companies which makes
sense it's like of course they've got
the most aggressive timelines it's like
we're going to map the human genome
faster as well too right so it's
interesting about where we are and I
think you know my we're not all the way
there but my intuition tells me we're
probably going to have a couple of
cracks at it actually uh on that
timeline so this is where we have to be
careful though you say commercial Fusion
you know what does that mean commercial
Fusion to me means that you're actually
have a known quantity about what it
costs what it costs to build and what it
costs to operate the reliability of
putting energy on the grid that's
commercial Fusion it's like so it turns
out that that's not not necessarily
exactly the first Fusion devices that
put electricity on the grid because you
got it there's a learning curve to get
like better and better at it but that's
probably I would suspect the biggest
hurdle is to get to the first one the
work I've done uh the work I continue to
do with autonomous vehicles and
semi-autonomous vehicles there's an
interesting parallel there where a bunch
of companies announced a deadline for
themselves in 2020 21 22 and only a
small subset of those companies have
actually really pushed that forward this
Google with waymo or alphabet rather uh
is do and and then there's uh
uh Tesla with semia Thomas driving in
their autopilot full self driving mode
and those are different approaches so
Tesla is achieving much much higher
scale but the sort of the quality of the
drive is semi-autonomous right I I don't
know if there's a metaphor or an analogy
here and then there's waymo that's
focusing on very specific cities but
achieving real full autonomy with actual
passengers but the scale is much smaller
so I wonder like just like you said
there would be these kinds of similar
kind of really hard pushes absolutely so
actually this is what I it's why I'm
encouraged about Fusion now so Fusion is
still hard let's let everyone be clear
because of the signs under underneath it
of us of achieving the right conditions
for the plasma basically is a is a is a
yardstick that you have to put up
against all of them what's encouraging
that I see in this and it's actually
what happens when you sort of let loose
the creativity of this is maybe I'll go
back to First principles so Fusion is a
also a fairly strange so if you think
about building a coal Point like burning
wood and coal and gas is actually not
that much different from each other
because they're kind of about the same
physical conditions and you get the fuel
and you light into the fusion is very
remember I told you that there's this
condition of the temperature which is
kind of universal
but if you take the density of the fuel
between magnetic fusion and inertial
fusion they're different by about a
factor of 10 billion
so this and the density fuel really
matters that actually so does the this
means energy confinement time is also
different by a factor of 10 billion as
well too because it's the product of
those two so one's really dense and
short lived and the other ones really
long-lived and and actually under dense
as well too
so what that means is that the way to to
the the way to the to get the underlying
physical state is so different among
these different approaches what it lends
itself to is does this mean that
eventual commercial products will
actually fill different needs in the
energy system so it sort of goes to your
comment about
because anything that is high tech and
is like a really important thing in our
economy tends to never find its way as
one only one manifestation like look at
Transportation as well too we have
scooters
Vespas you know uh Overland trucks cars
electric cars of course we have these
because they meet different demands in
it so what's interesting you know that I
find fascinating now is that we have
infusion it's going to look like that
that probably there's the while the
near-term focuses on electricity
production there might even be different
kinds of markets that actually make
sense in some places less than others it
comes to trade-offs because we haven't
really talked about the engineering yet
but engineering really matters like to
them to the operation of the device and
so it could be
um that that you know I suspect what
we'll end up with is several different
configurations which have different
features which are trade-offs basically
in in the energy Market whether he says
the major engineering
or general hurdles yeah that are in the
way yeah
um so the first one is just the cost of
building a single unit
so Fusion has and is actually
interesting you talked about the about
the different models that you have so
Fusion has
um one of its interesting limitations is
that it's very hard
almost at some point becomes physically
impossible to actually make small power
units
like a kilowatt a thousand Watts you
know which is like a personal home like
you know this is about a thousand
dollars or your personal use of an
energy of electricities but like a
thousand Watts
um this is basically impossible and if
for a single you know unit to do this
um so like you're not gonna have a
fusion like power plant like is your
furnace in or your electric heater in
your home and the reason for this comes
from the fact that Fusion relies on it
being it's not just that it's very hot
it says that the fusion power is the
heating source to keep it hot so if if
you get if you go too small it basically
just cannot keep it hot that's
um so it's interesting is that this so
this is one of the hard parts so this
means that the individual units you know
and it's it varies from concept to
concept but the the national academies
report that came out last year sort of
put the Benchmark as being like probably
the minimum size looks like around 50
million watts of electricity which is
like another for like a meat like a
small to you know mid-sized City
actually
um so that is so that's sort of like a
scale Challenge and in fact it's one of
the reasons why in Commonwealth and
another private sector ones like we they
try to push this down actually of trying
to get to the to these smaller units
just because it reduces the cost of it
um then probably
um obviously I would say it's an obvious
one like achieving the fusion State
itself and High Gain Is is a hard one
what we already talked about what kind
of harder what kind of challenges that
that's achieving the right temperature
density and energy confinement time in
the fuel itself in the plasma itself and
so some of the so some of the the
configurations which are being chosen
have are actually uh I have quite a ways
to go in fact I've seen those but what
their their consideration is oh yes but
by our particular configuration the
engineering Simplicity confers like an
economic Advantage even if we're behind
in sort of an assigned sense okay which
is fine this is also what you get when
you get a an explosion in in the private
sector you basically are Distributing
risks in different ways right which
makes sense
um all of that good that so what I would
say is that the the next hurdle to
really overcome is is about making that
electricity so like we need to see a
unit or several units like put using
Fusion in some way to put a meaningful
amount of energy on the grid because
this starts giving us real answers
um as to like what this is going to look
like the full end to end the full
end-to-end thing so Commonwealth's goal
is that I'll I'll just comment to
Commonwealth because I'll take some you
know some I get some credit for this is
that the the origins of Commonwealth
were in fact in examining that like we
could see this new technology coming
forward this this new superconducting
material and the origins of our thought
process were really around designing
effectively the pilot plant or the
commercial unit it's called Arc which is
actually the step forward after spark
and that was the orig the origins of it
so all the things that were other parts
of the plan like spark and the magnet
were actually all informed totally by
building something that's going to put
net electricity on the grid and the
timing of that we still hope is actually
the early 2030s so spark is the design
of the takamakan arc as the actual full
and thing it's like a thing that
actually puts the energy on the grid so
spark is named you know intentionally
that it's like it's on for a short
period period of time and it doesn't
have a it has yeah yeah you know it's
the spark of the fusion you know
Revolution or something like that I
guess we could call it um
yeah so those are those are so those are
sort of the programmatic challenges of
doing that and
um you know it's interesting you asked
about you talked about SpaceX so what
has evolved even in the last year or so
was in fact in March of 2022 the White
House announced that it was going to
start a program that kind of looks like
a SpaceX analogy that namely wow we've
got these things in the private sector
we should leverage the private sector
and the advantages of what they obtain
but also with the things like this is
going to be hard and it's going to cut
it's going to take quite a bit of
financing so why don't we set up a
program where we don't really get in the
way of the private sector Fusion
companies but we help them Finance these
difficult things which is how SpaceX
basically became successful through the
cots program fantastic right and that's
evolving as well too so like the fusion
ecosystem is almost unrecognizable from
where it was like five years ago around
those things how important is it for the
heads of the companies that are working
on nuclear fusion to have a Twitter
account and to be quite you said you
don't use Twitter I don't use that much
I mean there there is some element to
and I don't think this should be
discounted whatever you think about uh
figures like Jeff Bezos uh with blue
origin or Elon Musk or SpaceX
there is
a science communication yeah to put it
uh in nice terms that's kind of required
to really educate the public and get
everybody excited and sell the sexiness
of it I mean just even the videos of
SpaceX just being able to kind of get
everybody excited about going out to
space once again I mean there's all
kinds of different ways of doing that
but part I mean I guess most of the
companies do well you know is is to
advertise themselves to really sell
themselves it is yeah well actually it's
like I feel like one of the reasons on
this podcast and so like I I don't have
an official role in the company and one
of the reasons for for this was also
that it's interesting because when you
come from like you're running a company
it's it makes sense they're promoting
their own product and their own Vision
which totally makes sense but there's
also a very important role for academics
who have knowledge about what's going on
but are sufficiently distant from it
that they're not fully only so
self-motivated just by their own you
know projects or so forth and for me
this is I mean we we see particularly
the problems of the distrust in
technology
um and then honestly in the scientific
Community as well too it will be that
one of the greatest tragedies I would
say that if we go through all of this
and almost pull off what looks like a
miracle like Technologic and scientific
wise which is to make a fusion power
plant and then nobody wants to use it
because they feel that they don't trust
the people who are doing it or the
technology so we have to get so far out
ahead of this like so I give lots of
public lectures or things like this of
of accessing a larger range of people
we're not trying to hide anything you
can come and see you know come do tours
of our laboratory in fact I want to set
those up virtually as well too you might
look at our plasma size infusion center
YouTube channel so we are reaching out
through those meetings and it's really
important that we do those things but
it's also but also then realizing
setting up the realistic expectations of
what we need to do you know we're not
there like we don't have commercial
Fusion devices yet and you ask like what
are the challenges
I'm not going to get in into any deep
technical you know questions about what
the challenges are but it is it the
pathway not just to make fusion work
technically but to make it economically
competitive and viable so it is actually
used out in the private sector is a
non-trivial task and it's because of the
newness of it like we're simultaneously
trying to evolve the technology and make
it economically viable at the same time
those are two difficult couple tasks so
my own my own research and my own drive
right now is at Fantastic Commonwealth
Fusion systems is set up we have a
commercialization unit of that
particular kind which is going to drive
forward a token Mac in fact I was just
there there's discussions or there's
there's dialogues going on around the
world with other kinds of ones like
Stellar Raiders which prefer different
kinds of challenges and economic
advantages but what we have to I know
what we have to have what we have to
have is a new generation of integrated
scientists technologists and Engineers
that understand like how what needs to
get done to get all the way to the goal
line because we don't we don't have them
now like a multi-disciplinary yeah
exactly what's required I mean you've
spoken about uh you've said that Fusion
is quote the most
multi-disciplinary field you can imagine
yes yeah why why is that what are the
yeah well because because most of our
discussion that we've had so far is
really like a physics discussion really
so which don't don't
neglect physics is at the for origin of
this but I've already we touched on
plasma physics and nuclear physics which
are basically two you know somewhat
overlap but independent disciplines then
when it comes to the engineering it's
almost everything so so why is this well
let's build let's build an electromagnet
together okay what is this going to take
it's going to take
um it's basically electrical engineering
computer and so you under understand
what how it goes together and what
happens computational engineering to
model this very complex integrated thing
materials engineering because it's this
you're pushing materials to their limit
with respect to stress and so forth
takes cryogenic engineering which is
sort of a sub-discipline but cooling
things to extremely low temperatures
probably some kind of chemistry thing in
there too well actually yeah which tends
to show up in the materials and that's
just one of the sub components of it
like almost everything gets hit in this
right so you're and you're also in a
very integrated environment because in
the end all these things while you
isolate them from each other in a
physics sense in an engineering sense
they all have to work like seamlessly
together so it's one of those I mean in
my own career I've basically done Atomic
physics
spectroscopy you know plasma physics uh
iron etching
um
so this includes Material Science
um uh something called mhd even
magnetohydrodynamics and now all the way
through like I I'm not even sure how
many different careers I've had it's
also by the way this is also an um a
recruiting stage for like young
scientists thinking to come in like my
comment to sign is if you're bored in
Fusion you're not paying attention
because there's always something
interesting to go and and do so that's a
really important uh part of what we're
what we're doing which isn't new in
Fusion actually and in fact is in the
roots of of what we've done at MIT but
holy cow like the proximity
of of possibility of commercial Fusion
is the new thing you know so my
catchphrases like you might be wondering
like why aren't we doing all these
things like why weren't we pushing
towards economic fusion and new
materials and new methods of heat
extraction and so forth because
everybody knew Fusion was 40 years away
and now it's four years away there is a
history like you said 40 30 whatever
that kind of old joke uh there's a
history of fusion projects
that you know are characterized by cost
overruns and delays
um how do you avoid this how do you
minimize the chance of this you have to
build great teams
um uh is one of them it tends to be that
the smaller the there's sort of like I'm
not an expert in this but I've seen this
enough integrated certain equations yeah
well there's almost there's there's I've
seen this from enough teams like I've
seen also the futility of Lone Geniuses
trying to solve everything by themselves
like no but also organizations that have
10 000 people in them is is just not
doesn't lend itself at all to Innovation
so like one of our original sponsors and
a good friend vinod Coast I don't know
if you've ever talked to the node
Coastal he's a venture guy he's got
fantastic ideas about like the right
sizes of teams and things that really
innovate right and and there is an
Optimum place in there is that you get
enough cross-discipline and ideas but it
doesn't become so overly bureaucratic
that you can't execute on it so so one
of the ways and this was one of the
challenges of fusion is that everything
was leading towards like I have to have
like ex enormously large like teams just
to execute because of the scale of the
project the fact that now through
technology through both technology and
the argue financing Innovation we're
driving to the point where it's smaller
focused teams about doing those things
so that's one way to make it faster the
other way to make it faster is
modularize the problem or parse the
problem so this is the other difficulty
infusion is that it you know you tend to
look at this that's like oh it's it's
really just about making the plasma into
this state you know here that you get
this energy gain no because in the end
if you can parse out the different
problems of making that and then make it
as separate as possible from extracting
the energy and then converting it into
electricity the more separate those are
the better they are because you get
parallel pass that basically mitigate
risk this is not new infusion by the way
and this is the way that we attack most
complex technology logical
you know integrated technological
challenges have you uh by any chance
seen some of the application of
artificial intelligence reinforcement
learning a deep mind
has a nice paper has a nice effort
um on basically using reinforcement
learning for learn control algorithm for
for controlling nuclear fusion yeah um
do you find those kinds of I guess you
throw them under the umbrella of
computational modeling do you find those
interesting promising directions they're
all they're all interesting so when
people you know I'll pull back maybe a a
natural question is like why is it
different in Fusion like there's a long
history diffusion right it was going on
for like I told you like stories from
the late 1960s like what's different now
right so I I think from the from the
technology point of view there's two
massive things which are different so
one of them you know I'll be parochial
it's the Advent of this new
superconducting materials because the
most mature ways that we understand
about how we're gonna get the fusion
power plants or magnetic fusion and by
the fact that you've got access to
something which like changes the
economic equation by an over and Order
magnitude is just a totally you know and
that that wasn't that long ago was only
September of 2021 we actually
demonstrated the technology that changes
the the prospects there and the other
one is Computing and it's across the
whole Spectrum it's not just in control
of the fusion device it's actually in in
the we actually use machine learning and
things like this in the design of the
magnet itself it's an incredibly complex
design space so you use those tools the
simulation of the plasma itself is
actually we're at a totally different
place than we were because of those
things so those are the two big drivers
that I see actually that make it
different uh and actually and it's
interesting both those things self
enforce about what you asked about
before like how do you avoid delays and
things well it's by having smaller teams
that can actually execute on those but
now you can do this because the new
magnets make the devices all smaller and
the Computing means your Cuban
Effectiveness about exploring the
optimization space is way better it's
like they're all Interlink to each other
plus the modularization like you said
and so everything just kind of works
together to make smaller teams more
effective move faster and it's actually
and it's through that learned experience
I mean you know of the things that I'm
the most proud of about what came out in
fact the origins of thinking about how
we would use the the the high
temperature superconducting magnets came
out of my design class at MIT and in the
design class like one of the features
that I kept I mean it was interesting I
actually learned I really learned along
with the students about this but like
this insistence on the features like we
can't have so many coupled integrated
hard technology developments like we
have to separate these somehow so we
worked and worked and worked at this and
in fact that that's what really in in my
opinion the greatest advantage of the
arc design and when it com you know and
and built into the Commonwealth Fusion
system idea is like to parse out the
problems like how can we attack these in
parallel
um yeah and so it really comes to we
talked about philosophy it's like a
design philosophy like how do you attack
these these kinds of problems and you
know you do it like that and also like
you mentioned Offline that there's a
power to
you know as part of a class
yeah to decide a nuclear fusion uh
and it's it's hard to imagine a more
powerful force than like 15 MIT PhD
students like working together towards
solving a problem and what I always in
fact we just we recently just taught the
the most recent you know I say I teach
it I mean I I guide it actually the most
recent version of this where they
actually designed you know based on this
National academies report they actually
designed like the pilot plant that has
bases and similarities to what we had
done before but you know I kept wanting
to like push the envelope and where they
are it's like the creativity and the uh
and the the energy that they bring to
these things is kind of like it keeps me
going like us you know I'm not gonna
retire anytime soon when I keep seeing
that kind of dedication and it's
wonderful around on that um it almost
not to overuse a um uh uh or to
paraphrase something right which is that
you know the the famous
um uh quote by Margaret Mead you know
never doubt that a small group of
dedicated you know persons will change
the world indeed it's the only thing
that ever has I mean that's just such a
powerful and inspiring thing for an
individual find the right team be part
of that and then you yourself your
passion your efforts could actually make
a big change yeah a big impact I I gotta
ask you so it's
uh it's a whole nother different
conversation I'm sure to have but uh uh
nuclear power as it currently stands so
using uh fission uh is extremely safe
despite public perception it is the
safest actually so that's a whole nother
conversation but almost like a human
bureaucratic
physics
engineering uh question of what lessons
do you draw from the
um
catastrophic events where they uh the
the power plants did fail so Chernobyl
and Three Mile Island Chernobyl what
lessons do you draw three by London
wasn't really a disaster because nothing
escaped from the thing but Chernobyl and
Fukushima were have been you know had
obvious consequences in the populations
and that live nearby what lesson do you
draw from those that you can carry
forward to Fusion now I know there's you
can say that you're not going to have
the same kind of issues but it's
possible that the same folks also said
they're not going to be have those same
kind of issues yeah we humans the human
factor we haven't talked about that one
quite as much but it's still there so to
be clear it's so Fusion has the
intrinsic safety with respect to it
can't run away those are physics bases
Technology and Engineering basis of
running a complex again anything that
makes large amounts of power and heats
things up is got intrinsic safety in it
and by the fact that we actually produce
very energetic particles this doesn't
mean that there's no radiation involved
in ionizing radiation to be more
accurate infusion it's just that it's in
a very different order of magnitude
basically so what are the lessons uh in
in Fusion so so one of them is
make sure that you're looking at aspects
of the holistic environmental and
societal footprint that the technology
will have as technologists we tend not
to focus on these and particularly in
early stages of development like we just
want something that works right but if
we if we come with just something that
works but doesn't actually satisfy the
societal demands for safety and for
dispose I mean we will have materials
that we have to dispose of out of fusion
just this is but there's technological
questions about what that looks like so
will this look like something that you
have to you know put in the ground for
100 years or five years like and the
consequences of those are both economic
and societal acceptance and so forth but
don't bury those like put the bring
these up front talk to people about them
and make people realize that you're
actually you know the way I would look
is that you're making Fusion more
economically attractive by making it
more societally except as well too
and then realize is that you know I
think there's a few interesting you know
boundaries basically this so one of them
speaking of boundaries that successful
Fusion devices I'm pretty sure will
require that you don't have to re have
an evacuation plan for anybody who lives
at the site boundary
so this has this has implications for
what we build from a fusion engineering
point of view but has major implications
for where you can cite Fusion devices
right so in many ways it becomes more
like well you know we have fences around
you know industrial heat sources and
things like this for a reason right for
personal safety it looks more like that
right it's not quite as simple as that
but that's what it should look like and
in fact we have research projects going
on right now at MIT that are like trying
to push the Technologies to make it more
look like that I think that those are
key
and then in the end as I said like so
Chernobyl is physically impossible
actually in an effusion system I'm a
physics from a physics perspective you
can't run away like it did at Chernobyl
which was basically human error that you
know of letting letting the reactors
like run out of control essentially the
human error can still happen nuclear
with Fusion basically yeah so but in
that one if human error occurs then it
just stops and this is done and all of
those things this is the requirement of
of us as technologists and and
developers of this technology to not
ignore that dimension in fact of the
design and that's why me personally I'm
actually
pouring myself more and more into that
area because this is going to be I
actually really think it is an aspect of
the economic viability of fusion because
it clearly differentiates ourselves and
also sets this up to be about what we
want Fusion to be is that again on paper
Fusion can supply all of our energy like
all of it so this means I want it to be
like like really environmentally benign
but this takes engineering Ingenuity
basically to do that let me ask you some
wild out there questions sure so first
we've been talking too much you know
[Laughter]
simple uh practical things in everyday
life no the only revolutionizing the
entire energy infrastructure of human
civilization yes but
um so cold fusion yeah this this idea
this dream uh this interesting physical
goals seemed to be impossible uh but
perhaps it's possible do you think it is
possible do you think down the line
somewhere in
um
in the far distance as possible to
achieve Fusion at a low temperature
it's very very very unlikely and this
comes from so this would require a
pretty fundamental shift in our
understanding of of physics like as we
know it now and we know a heck of a lot
about how nuclear reactions occur
um but by the way what's interesting is
that there's they actually have a
different name for it they call it
leaner like low energy nuclear reactions
but we do have low energy nuclear
reactions we know these it's because
these come from particularly the weak
interaction the weak Force nuclear force
and so it's at this point
um
you know as a scientist you always keep
yourself open because but you also
demand proof right and that's the thing
it almost requires a breakdown on the
theoretical physics side so something
some deeper understanding about quantum
mechanics something so the quantum
tunneling some some weird yeah and that
and and people have looked at that but
even like something like Quantum
tunneling has a limit as to what it can
actually do so there there are people
who are genuine you know that really
want to see it make it but you know sort
of goes to the extraordinary I mean we
know Fusion happens at these high
energies like this when we know this
extremely accurately and I can show you
a plot that shows that as you go to
lower lower energy it basically becomes
immeasurable so if you're going down
this other pathway it means there's
really a very
different physical mechanism involved so
all I would say is that I I actually
poke in my head once in a while to see
what's going on and that area
um and as scientists we should always
try to make ourselves open
um and uh but in this one it's like but
show me something that I can measure and
that it's repeatable and then and then
it then it's going to take more
extraordinary effort and to date this
has not met that threshold in my opinion
so I'm even more so than just mentioning
or in that question thinking about
people that are claiming to have
achieved cold fusion I'm more thinking
even about
people who are studying black holes and
they're they're basically trying to
understand
the function of you know theoretical
physicists that are doing the Long Haul
yeah trying to investigate like okay
what is happening at the singularity
what is uh this kind of
uh holographic projections on a plate
these weird freaking things that are out
there in the universe and like somehow
accidentally they start to figure out
something weird yeah and then all of a
sudden there's weirdness all over the
place already yeah somehow that
weirdness will yeah I think in a time
scale probably of a hundred years or so
that weirdness will open
uh it just seems like nuclear fusion and
black holes and all of this are two
they're next door neighbors a little bit
too much for like you'll find something
yeah interesting let me tell you a story
about this yes okay it's a real story
okay
so they're a really really clever
scientists in the in the end of the late
1800s in the world you talk about like
James cork Maxwell when you talk about
Lord Calvin and you talk about Lawrence
actually who named after these other
ones and you on and on and on and like
Faraday and they discovered
electromagnetism holy cow and it's like
they figure out all these things and yet
there were these weird
things going on that you couldn't quite
figure out it's like what the heck is
going on with us right but we teach this
all the time in in physics classes right
so what was going on well there's just a
few
there's just a few kind of things things
unchecked but basically we're at the end
of Discovery because we figured out how
everything works because we've got we've
got basically Newtonian mechanics and
we've got Maxwell's equations which
describe basically how matter gets
pushed around and how electromagnetism
Works holy cow what a feat
there are these few nagging things
like for instance there's certain kinds
of rocks that for some reason like if
you put a photographic plate around it
it like it's burned or it gets an image
on it like well where's the
electromagnetism in that there's no
electromagnetic properties of this rock
oh yeah and the other thing too is that
if I if I take this wonderful classical
derivation of how a a something that is
hot about how it releases radiation
everything looks fantastic perfect match
oh until I get to high frequencies
of the light and then it basically just
the whole thing falls apart in fact it
gives a physical explanation which is
total nonsense it tells you that every
object should basically be producing an
infinite amount of heat and by the way
here's the Sun and we can look at the
Sun and we can figure out it's made out
of hydrogen and Lord Kelvin actually
made a very famous you know calculation
who was basically one of the founders of
thermodynamics so you look at the
hydrogen hydrogen has a certain energy
content that you know the latent heat
basically of hydrogen we know the mass
of the sun because we knew the size of
it and he conclusively proved that
basically there could only the the sun
could only make net energy for about two
or three thousand years
so therefore all this nonsense about
like deep is like because clearly the
sun can only last for two or three
thousand years if you think about the
captain this is basically the chemical
energy content of hydrogen and what
comes along in one decade
basically one guy sitting in a postal
office you know in Switzerland figures
out that all these you know Einstein of
course which was like figured out all
this create like took these these
seemingly unconnected things and it's
like boom there it is this is what it
was interest him but it was like there's
quantum physics like this explains this
other disaster and then this other guy
my hero
Ernest Rutherford experimentalist
did the most extraordinary experiment
which is like which was that okay they
had these funny rocks they emitted these
particles in fact they called them alpha
particles Alpha just a in the alphabet
right because it was the first thing
that they discovered
and what were they doing so they were
they were taking these alpha particles
and I by the way I do this to all my
students because it's a demonstration of
what you should be as a good scientist
so he took these Alpha things and he was
classically trained physicists knew
everything about momentum scattering and
so forth like that and he took this and
these Alpha which clearly were some kind
of energy but they couldn't quite figure
out what it was so so let's try to
figure that we'll actually use this to
try to probe the nature matter so he
took this
to these alpha particles and a very very
thin gold foil and so what you wanted to
see was that as they were going through
the way that they would scatter based on
classical in fact a coulomb collision
based on classical mechanics this will
tell me reveal something about what the
nature of the charge distribution is in
matter because they didn't know like
where the hell is this stuff coming from
even though they solved that
electromagnetism they didn't know like
what made up charges okay very
interesting on through it goes
and so what did you set up so it turns
out in the in these experiments what you
did was because if these out these
so-called Alphas which actually now we
know is something else as they go
through they would deflect how much they
deflect tells you how strong an electric
field they saw so you put detectors
because if you put if you put like a
piece of glass in front of this what
will happen is that when the alpha
particle hits it literally gives a
little a little bit of light like this
it's scintillates a little blue flash so
he would train his students or post like
whatever the heck they were at the time
you have to train yourself because you
have to put yourself in the dark for
like hours to get your eyes adjusted and
then they would start the experiment and
they would sit there and literally count
the things and they could see this
pattern developing which was revealing
about what was going on but there was
also another part to the experiment
which was that
it's like here's the alphas here's the
source they're going this way they could
tell they were going in One Direction
only basically they're going in this
direction
and you put all these over here because
you want to see how they deflect and
bend through it but you put a control in
the experiment but you basically put
glass particle glass glass plates back
here because obviously everything should
just deflect but nothing should bounce
back so it's a controlling experiment
but what did they see
they saw things bouncing back
like what the hell
like that fit no model of any idea right
but Rutherford like refused to like
ignore what was a clear like they
validated it and he sat down and based
on classical physics he made the most
extraordinary discovery which was the
nucleus
which is a very very strange Discovery
what what I mean by that because what he
could figure out from this is that in
order for these particles to bounce back
and hit this plate they were hitting
something that must be heavier than them
and that that basically something like
99.999 of the mass of the matter that
was in this gold foil was in something
that contained about one trillionth of
the volume of it
and that's called the nucleus
and until and you talk about so how
revealing is this is like this totally
changes your idea of the universe
because a nucleus is a very unintuitive
non-intuitive thing it's like why is all
the mass in something that is like zero
like it basically is the realization
that matter is empty it's all empty
space and that changes everything and it
changes everything until you had that
like you had steam engines by the way
you had Telegraph wires you had all
those things but that that realization
like opened up those two realization
opened up everything like lasers every
all you think about the modern world of
what we use
and that set it up so all I would point
out is that there's a story already that
sometimes there's these nagging things
at the edge of science that you know we
seem we Pat ourselves on the back and we
think we got everything under control
and of course that by the way that was
the origin of also that that it think
about this that was 1908 it took like
another 20 some years
before people put that together with
that's the process that's powering Stars
is the rearrangement of those nuclei not
atoms that's why Kelvin wasn't wrong he
just he was working with the wrong
assumptions right so of the fast forward
to today like what would this mean right
well there's a couple of things like
this that sit out there in physics and
I'll point out one of them which is very
interesting we don't know what the hell
makes up 90 of the mass in the universe
so that you know the search for dark
matter right what is it we still haven't
discovered it yeah ninety percent of the
mass of the universe is undetectable
like what and then you know then dark
energy and again black holes are the the
window into this as well then black hole
I mean sometimes black holes are way
better understood than those things as
well too so all it tells us is that we
shouldn't have hubris about the ideas
that we understand everything and when
we you know who knows what other the
next major intellectual Insight will be
about how the universe you know
functions and actually I think
Rutherford is the one who's attributed
at least that uh that quote that physics
is the only real science everything else
is stamp collecting right so uh there's
I'm so he's my hero but I'll slightly
disagree with that yes
well no off has a stamp collected that's
very important too
but you know that you have to have
humility about the kind of disciplines
that make progress at every stage in in
science in in science yeah that physics
did make a huge amount of progress in
the 20th century but it's possible that
other disciplines start to step in yeah
but Rutherford couldn't imagine like
mapping the human genome because we
didn't even know about DNA yeah or
computers really or computer you really
probably didn't think deeply about
computation it's like is it here's
here's a wild one what if like the next
great
Revelation to humanity about the
universe is not done by the human mind
that seems increasingly like more likely
and then you start to ask deep questions
about what is the purpose of science for
example
if
um AI system will design a nuclear
fusion reactor better than humans do but
we don't quite understand how it works
and they AI can't we know that it works
we can test it very thoroughly but we
don't know exactly what the control
mechanism is maybe what the chemistry
the physics is uh AI can't quite explain
it they just can't it's it's
impenetrable to our Consciousness
basically trying to hold it all together
and then and then okay so now we're
living in that world where many of the
biggest discoveries are made by AI
systems yeah
uh as if we weren't going big yeah I I
say you know it's again another point
out like when my when when my godmother
was born like none of this was in front
of us right it's like we live in an
amazing time it's like right like my
grandfather you know plowed you know
feels with a horse
I get to work on designing Fusion
reactors yeah yeah
pretty amazing time but still there's
humans so we'll see we'll see we'll see
if that's around 100 years maybe it'll
be yeah I think we're pretty resilient
actually yeah no that's that's one
lesson from life is it uh finds a way
yeah let me ask you in a bigger question
if is it as if those weren't big enough
let's look out
maybe a few hundred years maybe a few
thousand years out
there's something called the kardashev
scale it's a method of measuring
civilization's level of technological
advancement based on the amount of
energy it's able to use so type 1
civilization and this might be given all
your work is not no longer a scale that
makes quite make sense but it very much
focuses on the source of fusion natural
source of fusion which is for us the Sun
and type 1 civilizations are able to
Leverage
uh sort of collect all the energy that
hits Earth and then type 2 civilizations
are the ones that are able to Leverage
the entirety of the energy that comes
from the Sun by maybe building something
yeah so when will we reach type 1 status
is get to the level which were I think
maybe a few orders of magnitude away
from currently and in general do you
think about this kind of stuff because
where energy is so fundamental to this
like of life on Earth but also the
expansion of life into the universe oh
yeah so what one of the fun you know on
the on a weekend one I I sat down and
figured out what would it mean for
Interstellar travel like to have a DT
Fusion in fact one of the I talked about
my design class one of my design classes
was how you use
um essentially a special configuration
of a fusion device for not only
traveling to but colonizing Mars so
because what would you talk about energy
use being at the heart of civilizations
like so what if you want to go to Mars
not to just visit it but actually like
leave people there and make it something
happen and these massive amounts of
energy so what would that look like and
it actually transforms what how you're
thinking about doing that as well too oh
yeah so we we do all those kinds of fun
and actually it was a fairly you know
quasi-realistic actually so do you think
it'll be nuclear fusion that powers the
civilization on Mars well what we
considered was something so it turns out
that there's thorium
which is a heavy element so it's a
so-called fertile element that we know
what we still know fairly little about
the the geology of Mars and in the Deep
sense and we know that there's a lot of
this on the surface of Mars so one of
the things we considered was what would
happen that it's basically a combination
of a fusion device that actually makes
fuel from the thorium
oh but the under but the underlying
energy one was was Fusion itself as well
too so this is one of the examples of
being trying to be clever right around
those things or what is it you know this
also means it's like an Interstellar
travel it's like oh yeah that looks
almost like impossible basically from an
energy balance point of view it's just
because like the energy required to that
you have to transport to get there
almost the only things that would work
are DT fusion and basically um
Annihilation It's like Star Trek right
absolutely
your sense is that Interstellar travel
will require fusion power oh it's it's
almost even impossible with fusion power
actually it's so hard
it's so hard because you have to carry
the fuel with you and the rocket
equation tells you about how much fuel
you use to take so what you end up with
is like how long does it take to go to
these places and it's like staggering
you know periods of time so I I tend to
believe that there is alien
civilizations dispersed all throughout
yeah but we might have totally isolated
from them so you think we're not there's
none in this galaxy
so like and I guess and the question I
also have is what kind of do you think
they have nuclear fusion I was like is
it all yes the physics all the same yeah
oh the physics is all the same yeah
right so this is the and this is the
Fermi Paradox like where where the hell
is everybody in the universe right
um well there's some so you know the
scariest one of those is that I would
point out that there's been you know
there's you know order of many tens of
millions of species on the planet Earth
and only one ever got to the point of
sophisticated tool use that we could
actually start essentially leveraging
the power of what what's in nature to
our own will does this mean that
basically this means so almost look
there is almost certainly life or DNA
equivalence or whatever would be
somewhere I mean just because you just
need to soup and you need energy and you
get Organics and whatever the equivalent
of amino acids are but you know most of
life on Earth has been that those are
still amazing but it's still it's not
very interesting are we are we actually
the accident of History this is a very
interesting one they're super rare super
rare and then of course the other part
is that also just the other scary part
of it which is if you look at the fairy
paradoxes good good we got to this point
how long has it been in humans so humans
Homo Sapien has been around for whatever
100 000 years 200 000 years
um our ability in in that timeline to
actually make an imprint on the universe
like for by emitting radio waves or by
modifying you know in nature in a
significant way has only been for about
a hundred of those hundred thousand
years
and you know are we it's a good question
so is it by definition that by the fact
that when you are able to reach that
level of being able to manipulate nature
and for example discover you know
discover like fission or or or other or
or burning fossil fuels and all this is
that what it says oh you're doomed
because by definition any species that
gets to that point that can modify their
environment like that they'll actually
push themselves
you know past that's that's one of the
most depressing scenarios that I can
imagine yeah so the the so basically
we're we will never line up in time
because you get this little teeny window
in time over civilization might occur
and you you can never see it because you
never these these sort of like scatter
like like fireflies around the Galaxy
and you never yeah yeah
and then explodes it destroys itself
because of the potential and when we say
destroy ourselves all we would have to
do is that we basically go if you humans
are all left and we're still living on
the planet and but all we have to do is
go to the technology of like you know
1800 yeah and we're invisible in the
universe again
yeah he so it was when I when I listened
to the part I I thought I wanted to talk
about this as well too because this it
comes from well it comes from a science
point of view actually of what it means
but also to me it's like another
compelling driver of telling us it's
like why we should try really hard not
to screw this up like we're in this
unique place of our ability to discover
and make it and I just don't want to
give up about thinking that we can get
through yeah I tend to see that there is
some kind of game theoretic Force like
with Demetrius shared destruction that
ultimately in each human being there's a
desire to survive and a willingness to
cooperate to have compassion for each
other in order to survive and I think
that I mean maybe not in humans but I
can imagine nearly infinite number of
species in which
that overpowers
any uh technological advancement that
can destroy or rewind the species so I
think if humans fail
I hope they don't
I see a lot of evidence for them not but
it seems like somebody will survive and
there you start to ask questions about
why why we haven't met yet maybe it's
just space is large oh spaces it's I I
think in logarithms and I can't even
fathom you know space this is
extraordinary right yeah it's
extraordinarily large yeah I mean
there's so many places on Earth I just
recently visited Paris for the first
time yeah and there's so many other
places I haven't visited there's so many
other places well I like to you know
it's interesting that we have this
fascination with alien life we have what
is essentially alien life on Earth
already like you think about the
organisms that develop around deep sea
like thermal vents one of my favorite
books of all time from Stephen J Gould
if you've never read that book it kind
of blows your mind it's about the
Cambrian explosion of life and it's like
oh you look at these things and it's
like our the chance of us existing as a
species like the the genetic diverse
city was larger back then you know this
is about five about 500 million years
ago or something like that it is a
mind-altering trip of thinking about our
place in the universe I have to say plus
the Mind itself yeah is the kind of
alien but almost
um
almost a mystery to ourselves we still
don't understand it the very the very
mechanism that helps us explore the
world is still a mystery yeah so that
like understanding that will also unlock
um a quite quite possibly unlock our
ability to understand the world and
maybe build machines that help us
entertain the world build tools then I
mean it already has I mean our ability
to understand the world is is ridiculous
almost Ashley
[Laughter]
so what uh advice would you give to uh
young folks or folks of all ages or lost
in this world looking for a way looking
for a career they can be proud of or
looking to have a life they can be proud
of yeah oh the first thing I would say
is don't give up I get to see uh
multiple sides of this and you know
there's there seems to be
um a level of Despair in a Young
Generation it's like you know it's it's
almost like the Monty Python skit like
I'm Not Dead Yet right I mean yeah like
we're we're not there we're we're in a
place that you know in in you know you
know don't say the world's going to end
in 300 days or something it's not okay
and when we mean by this is that we have
a robust Society that's figured out how
to do like amazing things and we're
gonna keep doing amazing things but that
shouldn't be complacency
about what our future is and the future
for their children as well too and in
the end I mean it's a very it's a
staggering Legacy to think of what we've
built up primarily by basically using
carbon fuels like people almost tend to
think of this as an evil thing that
we've done I think it's an amazing thing
that we've done but we owe it to
ourselves and um and and to this thing
that we've built let me talk about the
end of the world is this nonsense what
it is is it's the end of this kind of
lifestyle and civilization at this scale
and the ability to execute on these
kinds of things that we were talking
about today like we are extraordinarily
privileged we are in a place where it's
just it's it's almost unfathomable
compared to most of the the misery that
humans have lived in for our history so
don't give up about this okay but also
roll up your sleeves and let's get going
at solving and getting real solutions to
the problems that are in front of us
which are significant you know it's I
would most of them are linked to how
what we use in energy but it's not just
that it's it's around all the aspects of
like what does it mean
like what does it mean to have a
distributed energy source that lifts
billions of people out of poverty you
know particularly outside of like the
Western Nations right that seems to me a
pretty compelling you know moral goal
for our for all of us
um but particularly for this upcoming
you know uh generation and then the
other part is that is that we've got
possible solutions in front of us apply
your talents in a way that that that
you're passionate about and is going to
make a difference
and that's only possible with the
optimism hope and hard work yeah what uh
easy question
certainly easier than nuclear fusion
what's the meaning of life why are we
here 42 is it 42 no no
um we already discussed about the beauty
of physics that there's almost a desire
to ask a why question about why the
parameters have these values yeah
it's very tempting yeah it's it's an
interesting
hole to go down as a scientist because
we're a part of what people have a hard
time people who aren't scientists have a
hard time understanding what scientists
do to themselves and a great scientist
does a very non-intuitive or non-human
thing what we do is we train ourselves
to doubt ourselves like hell like that's
a great scientist we doubt everything we
see we doubt everything that we think
because we we try to we we basically try
to turn off the belief valve right that
humans just naturally have
um so when it comes to these things like
I can I can make my own comments to this
is like personally you see these things
about the ratios of life and I made a
comment where I said well you know a
wrap my some part of my brain that just
goes Yeah well yeah because we're the
only interesting you know Multiverse
because by definition it has to look
like this you know
but there's I have to say there's other
times I can say in the history of the
whole of what has happened over the last
10 years there have been some pretty
weird coincidences like coincidences
that like you look at it and just go is
that really was that really a
coincidence
is something like pushing us toward
towards these things and it's a natural
it's a human instinct because you know
since the beginnings of humanity we've
always assigned you know you know human
motivation and and and needs to these
somewhat you know empirical observations
and in some sense the stories
before we understand the real
explanations the stories the myths uh
Service as a as a good approximation
yeah for the thing that we're yet to
understand absolutely and in that sense
you said the antithesis to sort of
scientific doubt is is having a faith in
these stories they're almost
silly when uh looked at from a
scientific perspective but just even the
feelings of it seems that love is a
fundamental fabric of human uh condition
and what the hell is that
as the physicist I go it's you know this
is this is a repeatable thing that's due
to a set of synapses that fire in a
particular pattern and all this yes you
know that's kind of like okay man what a
you know what a drag that is right to
think of it this way and you can have an
evolutionary biology explanation but
there's still a magic to it I mean I see
scientists I have some of my colleagues
you know do this as well too like where
what what is spirituality compared to
science and so forth I my own my own
feeling in this is that
you know as a scientist because I've had
the pleasure of being able to like both
understand what my predecessors did but
I also had the privilege of being able
to discover things right as a scientist
and
and I see that and you just in just in
just the range of our conversations like
that is my in a weird way my it's the
awe that comes from looking at that that
is if you're not in awe of the universe
and nature you haven't been paying
attention I mean my own personal feeling
is that I feel
uh if I go if I go snorkeling on a coral
reef I feel more awe than I could ever
feel like in a in a church you kind of
notice some kind of magic there there's
something about the way the whole darn
thing holds together that just sort of
escapes your imagination and that's to
me the this thing of and then we have
different words we call them holistic or
spiritual the way that it all hangs
together in fact one of the interesting
things you asked about like what I think
about well the craziest things that I
think that how does it hold together is
like our society like how does oh look
what yeah like how because there's no
way like you just think of the United
States there's 330 million people kind
of working like this engine about going
towards making all these things happen
but there's like no one in charge of
this really not really yeah how the how
the heck does this happen it's kind of
like it's so the these things these are
the kinds of things mathematics
automatically and organization wise that
I think of just because they're they're
sort of they're awe-inspiring and
there's different
ideas that would come up together we
share them and then there's uh there's
teams of people that share different
ideas and those ideas compete like
there's the ideas themselves are these
kinds of different organisms and
ultimately somehow we build Bridges and
and nuclear reactors and do those things
well I have to give a shout out to my
daughter by the way who's who's
interested she's an applied math major
and she's she's amazing at math and over
the break she was showing she's doing
researches it's basically about how
ideas and Ethos are transmitted within a
society nice so she's building an
applied math model who's explaining like
she was showing me on this like the
simulation she goes oh look look at this
and I said oh oh that's like how
political parties like evolve right yeah
and even though it was a rather you know
quote-unquote simple math mathematical
model it wasn't really it's like oh wow
well maybe she has a chance to derive
mathematically the the answer to the
what's the meaning of life there we go
and maybe it is indeed 42. well
um Dennis thank you so much for just
doing
creating tools creating systems
exploring this idea
that's one of the most amazing magical
ideas in all of uh human endeavor which
is nuclear fusion I mean that's so
interesting you know it's almost like my
one of my lifelong goals is like to make
it it's like it's not magic it's like
it's as boring as all heck
and this means we're using it everywhere
right yeah yeah and the magic is then
built on top of it yeah well thank you
for everything you do uh thank you for
talking to me it's a huge honor this is
a fascinating and amazing conversation
thank you
thanks for listening to this
conversation with Dennis white to
support this podcast please check out
our sponsors in the description and now
let me leave you with some words from
Albert Einstein
there are two ways to live your life
one is as though nothing is a miracle
the other is though everything's a
miracle
thank you for listening I hope to see
you next time