Kind: captions
Language: en
so you have an original life event it
evolves for 4 billion years at least on
our planet it evolves a technosphere the
Technologies themselves start having
this property we call life which is the
phase we're undergoing now it solves the
origin of itself and then it figures out
how that process all works understands
how to make more life and then can copy
itself onto another planet so the whole
structure can reproduce
itself the following is a conversation
with Sarah Walker her third time in the
podcast she is an astrobiologist and
theoretical physicist interested in the
origin of life and in discovering alien
life on other worlds she has written an
amazing new upcoming book titled life as
no one knows it the physics of life's
emergence this book is coming out on
August 6th so please go pre-order it now
it will blow your mind this is Al Le fre
podcast to support it please check out
our sponsors in the description and now
dear friends here's Sarah
Walker you open the book life as no one
knows it the physics of life's emergence
with a distinction between the
materialists and the vitalists so what's
the difference can you maybe Define the
two I think the question there is about
whether life can be
described in terms of matter and you
know physical physical things or whether
there is
some other feature that's not physical
that actually animates living things so
for a long time people maybe have called
that a soul it's been really hard to pin
down what that is so I think the
vitalist idea is really that it's it's
kind of a dualistic interpretation that
there's sort of the material properties
but there's something else that animates
life that is there when you're alive and
it's not there when you're dead and
materialists kind of don't think that
there's anything really special about
the matter of life and the material
substrates that life is made out of so
they disagree in some really fundamental
points is there a gray area between the
two like maybe all there is is matter
but there's so much we don't know that
there might as well be magic that that
like whatever that magic that the
vitalists see meaning like there's just
so much mystery that it's really unfair
to say that it's boring and understood
and as simple as quote unquote physics
yeah I think the entire universe is just
a giant mystery um I guess that's what
motivates me as a scientist and so often
times when I look at open problems like
the nature of life or Consciousness or
you know what is intelligence or are
there souls or whatever whatever
question that we have that we feel like
we aren't even on the tip of answering
yet I think you know we have a lot more
work to do to really understand the
answers to these questions so it's not
magic it's just the unknown and I think
a lot of the history of humans coming to
understand the world around us has been
taking ideas that we once thought were
magic or Supernatural and really
understanding them in a much deeper way
um that we learn what those things are
and they still have an air of mystery
even when we understand them there's
there's no there's no sort of bottom to
our understanding
so do you think the vitalists have a
point that they're uh more eager and
able to notice the magic of life I think
that no tradition vitalists included is
ever fully wrong about the nature of the
things that they're describing so a lot
of times when I look at different ways
that people have described things across
human history across different cultures
there's always a seed of Truth in them
and I think it's really important to try
to look for those because if there are
narratives that humans have been telling
ourselves uh for thousands of years for
thousands of generations there must be
some truth to them you know we've been
learning about
reality um for a really long time um and
we recognize the patterns that reality
presents us we don't always understand
what those patterns are and so I think
it's really important to pay attention
to that so I don't think the vitalists
were actually wrong and a lot of what I
talk about in the book but also I think
about a lot just professionally is the
nature of our definitions of what's
material and how science has come to
invent the concept of matter and that
some of those things actually really are
inventions that happened in a particular
time in a particular technology that
could learn about certain patterns and
help us understand them and that there
are some patterns we still don't
understand and if we knew how
to uh measure those things or we knew
how to describe them uh in a more
rigorous way we would realize that the
material World matter has more
properties than we thought that it did
and one of those might be associated
with the thing that we call life life
could be a material property and still
have a lot of the features that the
vitalist thought were mysterious so we
may still expand our understanding what
is Incorporated in the category of
matter that will eventually incorporate
such magical things that the vitalists
have noticed like life yeah so I think
about um I always like to use examples
from physics so I'll
do that to like like it's just my it's
my go-to place um but you know in in the
history of gravitational physics for
example in the history of motion you
know like when Aristotle came up with
his theories of motion he did it by the
material properties he thought things
had so there was a concept of things
falling to Earth because they were solid
like and things raising to the heavens
because they were air likee and things
moving around the planet cuz they were
Celestial like but then we came to
realize that thousands of years later
and after the invention of many
technologies that allowed us to actually
measure um time in a mechanistic way and
track planetary motion uh and we could
you know roll balls down incline planes
and track that progress we realized that
if we just talked about mass and
acceleration we could unify all Motion
in the universe in a really simple
description um so we didn't really have
to worry about the fact that my cup is
heavy and the air is light like the same
laws describe them um if we have the
right material properties to talk about
what those laws are actually interacting
with and so I think the issue with life
is we don't know how to think about
information in a material way and so we
haven't been able to build a unified
description of what life is or the kind
of things that Evolution builds um
because we haven't really invented the
right material concept yet so when
talking about motion the laws of physics
appear to be the same everywhere in the
universe you think the same is true for
other kinds of matter that we might
eventually include life
in I think life obeys Universal
principles I think there is some deep
underlying exploratory framework that
will tell us about the nature of life in
the universe and will allow us to
identify life that we can't yet
recognize um because it's too different
you write about the Paradox of the
finding life why does it seem to be so
easy and so complicated at the same time
you know all the sort of classic
definitions people want to use just
don't work they don't work in all cases
so uh Carl Sean had this wonderful essay
on definitions of life where I think he
talks about aliens coming from another
planet if they saw Earth they might
think that cars were the dominant life
form because there's so many of them on
our planet and like humans are inside
them and you might want to exclude
machines uh but any definition you know
like classic biology textbook
definitions would also include them and
so you know he wanted to draw a boundary
between uh these kind of things by
trying to uh exclude them but they were
naturally included by the definitions
people want to give and in fact what he
ended up pointing out is that all of the
definitions of life that we have whether
it's life is a self-reproducing system
or life eats to survive or life requires
compartments whatever it is there's
always a counter example that challenges
that definition this is why viruses are
so hard or why fire is so hard and so uh
we've had a really hard time trying to
pin down from a definitional perspective
exactly what life is yeah you actually
bring up the the zombie an fungus I
enjoyed looking at this thing as an
example of one of the challenges
mentioned viruses but this this is a
parasite look at that did you see this
in the jungle infects ants actually one
of the interesting things about the
jungle Jungle everything is Emeral like
everything eats everything really
quickly so if you uh if an organism dies
uh that organism disappears isn't yeah
it's a machine that doesn't have
uh I wanted to say doesn't have a memory
or history which is interesting given
your work on history in defining a
living being the jungle forgets very
quickly it wants to erase the fact that
you existed very quickly yeah but it
can't erase said it's just restructuring
it and I think the other thing that is
really you know Vivid to me about this
example that you're giving is how much
death is necessary for life so I I worry
a bit about um Notions of immortality
and whether immortality is a good thing
or not um so I have sort of a broad
conception that life is the only thing
the universe uh generates that actually
has even the potential to be immortal
but that's as like this sort of process
that you're describing where life is
about memory and historical contingency
and construction of new possibilities
but when you look at any instance of
life especially one as dynamic as what
you're describing it's a constant birth
and death process but that birth and
death process is like the way that the
Universe can explore what possibilities
can exist and not everything not every
possible human or every possible ant or
every possible zombie ant or every
possible tree will ever live so it's uh
you know it's an incredibly Dynamic and
creative place because of all that death
so does this thing this is a parasite
that needs the ant so is this a living
thing or is this not a living thing so
this is yeah so it just pierces the ant
I mean it it right and I've seen a lot
of this by the way um organisms working
together in the jungle like ants
protecting a delicious piece of fruit so
they need the fruit but like if you
touch that fruit they're going to
like the forces emerge they're fighting
you they're defending that fruit right
to the death it just nature seems to
find mutual benefits right yeah it does
um I I think the thing that's perplexing
for me about these kind of examples is
you know effectively the ant's dead but
it's staying alive now because it's
piloted by this fungus and so that gets
back to this you know thing that we were
talking about a few minutes ago about
how the boundary of life is really hard
to Define so you know anytime that you
want to draw a boundary around something
and you say this feature is the thing
that makes us alive or this thing is
alive on its own there's not ever really
a clear boundary and these kind of
examples are really good at showing that
because it it's like the thing that you
would have thought is the living
organism is now dead except that it has
another living organism that's piloting
it so the two of them together are alive
and some sense but they're you know now
in this kind of weird symbiotic
relationship that's taking this an to
its death so what do you do with that in
terms of when you try to Define life I
think we have to get rid of the notion
of an individual as being
relevant and this is really difficult
because you know a lot of the ways that
we think about life like the fundamental
unit of life is the cell individuals are
alive um but we don't think about how
how gray that distinction is so for
example um you might consider you know
self- reproduction to be the most most
defining feature of Life a lot of people
do actually like you know one of these
standard different definitions that a
lot of people may feel like to use in
astrobiology is life is a
self-sustaining chemical system capable
of darwinian evolution which I was once
quoted as agreeing with and I was really
offended um because I hate that
definition I think it's terrible um and
I think it's terrible that people use it
I think like every word in that
definition is actually wrong as a
descriptor of life life is a
self-sustaining chemical system capable
of darwinian evolution why is that that
seems like a pretty good yeah I know if
you want to make me angry you can
pretend I said
that and believed it so self- sustaining
uh chemical system darwinian Evolution
what is self- sustaining what's what
what's so frustrating I mean which
aspect is frustrating to you but it's
also those are very interesting words
yeah they're all interesting words um
and you know together they sound really
smart and they sound like they box in
what life is but you can use any of this
any of the words individually and you
can come up with counter examples that
don't fulfill that property the self
sustaining one is really interesting
thinking about um humans right like
we're not self- sustaining we're
dependent on societies and so you know I
find it paradoxical that you know it
might be that societies because their
self-sustaining units are now more alive
than individuals are and that could be
the case but I still think we have some
property associated with life I mean
that's the thing that we're trying to
describe so that one's quite hard and in
general you know no organism is really
self- sustaining they always require an
environment so being self-sustaining is
coupled in some sense to the world
around you uh we don't live in a vacuum
um so so that part's already challenging
and then you can go to chemical system I
don't think that's good either I think
there's a confusion because life emerges
in chemistry that life is chemical I
don't think life is chemical I think
life emerges in chemistry because
chemistry is the first thing the
universe builds where it cannot exhaust
all the possibilities because the
combinatorial space of chemistry is too
large well but is it possible to have a
life that is not a chemical system yes
well there's a guy I know named Lee
Cronin has been on a podcast a couple
times who just got really pissed off
listen he probably got really pissed off
hearing that I for people somehow don't
know he's a chemist yeah but he would
agree with that statement would he I
don't think he would I don't think he
would he would broaden the definition of
chemistry until it would include
everything oh sure okay so you or maybe
I don't know but wait but you said that
universe that's the first thing it
creates is chemistry we're the very
precisely it's not the first thing it
creates obviously like it has to make
atoms first but it's the first thing
like if you think about you know the
universe originated uh atoms were made
in you know Big Bang nuclear synthesis
and then later in stars and then planets
formed and planets become engines of
chemistry they start exploring what kind
of chemistry is possible and the
combinatorial space of chemistry is so
large that even on every planet in the
entire universe you will never express
every possible molecule um I I like this
example actually that that Lee gave me
which is to think about taol it has a
molecular weight about
853 it's got you know a lot of atoms but
it's not astronomically large and if you
try to make um one molecule uh with that
molecular formula in every
three-dimensional shape you could make
with that molecular formula it would
fill
1.5 universes in volume so that with one
unique molecule that's just one molecule
so chemical space is huge um and I think
it's really important to recognize that
because if you want to ask a question of
why does life emerge in chemistry well
life emerges in chemistry because life
is the physics of how the universe
selects what gets to exist um and those
things get created along historically
contingent pathways and memory and all
the other stuff that we can talk about
um but the universe has to actually make
historically contingent choices in
chemistry because it can't exhaust all
possible molecules what kind of things
can you create that's outside the the
combinatorial space of chemistry that's
what I'm trying to understand oh if it's
not chemical so I think some of the
things that have evolved on our
biosphere I would call as much alive as
chemistry as a cell um but they seem
much more abstract so for example I
think language is alive I think um or at
least life um I think memes are I think
you're saying language is life yes
language is alive oh boy I'm going to
have to explore that
one okay life Maybe not maybe not alive
but I don't I actually I don't know
where I stand exactly on that um I've
been thinking about that a little bit
more lately but mathematics too um and
it's interesting because people think
that math has this platonic reality that
exists outside of our universe and I
think it's a feature of our biosphere
and it's telling us something about the
structure of
ourselves um and I find that really
interesting because when you would sort
of internalize all of these things that
we notice about the world and you start
asking well what do these look like if I
was you know something outside of myself
observing these systems that we're all
embedded in what would that structure
look like and I think we look really
different than the way that we talk
about what we look like to each other
what do you think a living organism in
math is is it one exatic system or is it
individual theorems or is
it the fact that it's um open-ended in
some sense it's it's another open-ended
uh combinatorial space and the recursive
properties of it allow creativity to
happen uh which is what you see with you
know like the revolution in the last
century with girdle theorem and Turing
and you know there's there's clear
places is where mathematics notices
holes in the universe so it seems like
you're sneaking up on a different kind
of definition of Life open-ended large
combinatorial space yeah room for
creativity definitely not chemical I
mean chemistry is one subed to chem
chemical okay what about the third thing
which I think would be the the hardest
CU you probably like it the most is
evolution or selection well specifically
it's darwinian Evolution and I think
darwinian evolution is a problem but the
reason that that definition is a problem
is not because evolution is in the
definition but because the implication
is that you know that PE most people
would want to make is that an individual
is alive and The evolutionary process at
least the darwinian evolutionary process
most evolutionary processes they don't
happen um at the level of individuals
they happen at the level of populations
so again you would be saying something
like what we saw with the self-
sustaining definition which is that
population are alive but individuals
aren't because populations evolve and
individuals don't and obviously like
maybe you're alive because you know your
gut microbiome is evolving but Lex as an
entity right now is not evolving by
canonical theories of evolution in
assembly Theory which is attempting to
explain life evolution is a much broader
thing so so in an an individual organism
can evolve under assembly theory yes
you're constructing yourself all the
time assembly theory is about
Construction How the Universe selects
for things to exist what if you
reformulate everything like a population
is a living organism so that's fine too
but but this again gets back to so um so
I think what all of the you know like we
can nitpick at definitions I don't think
it's like incredibly helpful to do it
but the reason for for me fun yeah it is
fun it is really fun and actually do I
do think it's useful in the sense that
when you see the way the ways that they
all break down um you either have to
keep forcing in your like sort of
conception of life you want to have or
you have to say all these definitions
are breaking down for a reason maybe I
should adopt a more expansive definition
that encompasses all the things that I
think and are life and so for me I think
life is the process of how information
structures matter over time and space
and an an example of life is what
emerges on a planet and yields an
open-ended Cascade of generation of
structure and increasing complexity and
this is the thing that life is and any
individual is just a particular instance
of these
lineages that are you know structured
across time um and so we focus so much
on these individuals that are these
short temporal moments in this L larger
causal structure that actually is the
life on our planet um and I think that's
why these definitions break down because
they're not General enough they're not
Universal enough they're not deep enough
they're not abstract enough to actually
capture that regularity cuz were focused
on those that little affir thing that we
call human life Aristotle focusing on
you know heavy things falling because
they're earthlike and you know things
floating because they're air likee it's
the wrong thing to focus on so what what
exactly are we missing by focusing on
such a short span of time I think we're
missing most of what we are so one of
the issues I've been thinking about this
all like really viscerally lately it's
weird when you do theor physics cuz I
think it like literally changes the
structure of your brain and you see the
world differently especially when you're
trying to build new abstractions do you
think it's possible if you're a
theoretical physicist that like it's
easy to fall off the cliff and go
descend to Madness I mean I think you're
always on the edge of it but I think
what is amazing about being a scientist
um and trying to do things rigorously is
it keeps your sanity so I think if I
wasn't a theoretical physicist I would I
would be probably not saying
um but what it forces you to do is hold
the like you have to hold yourself to
the fire of like these abstractions in
my mind have to really correspond to
reality and I have to really test that
all the time and so I love building new
abstractions and I love going to those
like incredibly
creative uh you know spaces that people
don't
see um as part of the way that we
understand the world now but ultimately
I have to make sure that whatever I'm
pulling from that space is something
that's really usable and really like
relates the world outside of me that's
what science is so we were talking about
what we're missing when we look at a
small stretch of time in a small stretch
of space yeah so the issue is um we
evolve perception to see reality a
certain way right so for us Space is
really important and time feels bleeding
and I I you know I had a really
wonderful Mentor Paul Davies most of my
career and Paul's amazing because he
gives these like little he thought
experiments all the time like you know
something he used to ask me all the time
was when I was a postto this is kind of
a random tangent but was like you know
how much of the universe be could be
converted into technology if you were
thinking about like you know long-term
Futures and stuff like that and it's
like a weird thought experiment but like
there's a lot of deep things there I do
think a lot about the fact that we're
really limited in our interactions with
reality by the particular architectures
that we evolved um and so we're not
seeing everything and in fact our
technology tells us the solid time
because it allows us to see the world in
new ways um by basically allowing us to
perceive the world in ways that we
couldn't otherwise and so what I'm
getting at with this is I think that
living objects are actually huge like
they're some of the biggest structures
in the universe but they are not big in
space they are big in time and we
actually can't resolve that feature we
don't interact with it on a regular
basis so we see them as these fleeting
things that have this really short
temporal clock time without seeing how
large they are when I'm saying time here
I really like the way that people could
picture it is in terms of causal
structure so if you think about the
history of the universe to get to you
and you imagine that that entire history
is you that is the I the picture I have
in my mind when I look at every living
thing so you have a you have a tweet for
everything you tweeted doesn't everyone
you have a lot of poetic profound tweets
um sometimes
they're
puzzles that take a long time to figure
out well you know what it is the trick
is the reason they're hard to write is
because it's compressing a very deep
idea into a short amount of space and I
really like doing that intellectual
exercise because I find it productive
for me yeah it's a very interesting kind
of compression algorithm though yeah I
like language I think it's really fun to
play with yeah I wonder if AI can uh
decompress it that' be
interesting I would like to try this but
I think I use langu anguage in certain
ways that are non-canonical and I do it
very purposefully and it would be
interesting to me how AI would interpret
it yeah your tweets would be a good
touring test for this for super
intelligence anyway you tweeted that
things only look
emergent because we can't see time mhm
so if we could see time what would the
world look like you're saying you'll be
able to see everything that an object
has been every step of the way that led
to this current
moment and all the interactions that
required to make that Evolution happen
so you would see this gigantic Tale the
universe is far larger in time than it
is in space yeah and this planet is one
of the biggest things in the universe
also the more complexity the
bigger yeah Tech technosphere I think
the the modern technosphere is the
largest object in time in the universe
that we know about and when you say
technosphere what do you mean I mean uh
the global integration of life and
Technology on this planet so all the
things all the technological things we
created but I don't think of them as
separate they're like very integrated
with the structure that generated them
so you can almost imagine it like time
is constantly bifurcating and it's
generating new structures and these new
structures are um you know locally
constructing the future and so things
like you and I are very close together
in time because we didn't diverge like
very early in the history of universe
it's very recent um and I think this is
one of the reasons that we can
understand each other so well and we can
communicate effectively um and I might
have some sense of what it feels like to
be you but you know other organisms um
bifurcated from us in time earlier this
is just the concept of philogyny right
um but if you take that deeper and you
really think about that as the structure
of the physics that generates life um
and you take that very seriously all of
that causation is is still bundled up in
the objects we observe today and so um
so you and I are are close in this
temporal structure but we're also um
we're so close because we're really big
and we only are very different in sort
of like the most recent moments in the
time that's like Ed in
us uh it's hard to use words to
visualize what's in
Minds I have such a hard time with this
sometimes I'm like I like I actually I
was thinking on the way over here I was
like I like you know you have pictures
in your brain and then they're hard to
put into words but I realized I always
say I have a visual but it's not
actually I have a visual it's I have a
feeling because oftentimes I cannot
actually draw a picture in my mind for
the things that I say but times they go
through a picture before they get to
words but I like experimenting with
words because I think they help paint
pictures yeah it's again some kind of
compressed feeling that you can query to
get a a sense of the bigger
visualization that you have in mind it's
just a really nice
compression but I think the idea of this
object that in it contains all the
information about the history of an
entity that you see now just trying to
visualize that is pretty cool yeah it's
I mean obviously the Mind breaks
down quickly as you step seconds and
minutes back in time but for
sure I guess it's just a
gigantic object yeah supposed to be
thinking about yeah I think so and I
think this is one of the reasons that we
have such an ability to abstract um as
humans because we are so gigantic that
like the space that we can go back into
is really large so like the more
abstract you're going like the you're
going in that space But in that sense
aren't we fundamentally all connected
yes and this is why the the definition
of Life cannot be the individual it has
to be these lineages because they're all
connected they're interwoven and they're
exchanging Parts all the time yeah so
maybe there's certain aspects of those
lineages that can be lifelike they can
be characteristics that can be measured
like with the sun theory that have more
or less life but they're all just
fingertips of
a of a much bigger object yeah I think
is very high dimensional and in fact I
think you can be alive in some
dimensions and and not in others like if
you could if you could project all the
causation that's in you in some in some
features of you you know very little
causation is required and like very
little history and in some features a
lot is so it's quite difficult to take
this really
high-dimensional uh very deep structure
and project it into things that we
really can understand and say like this
is the one thing um that we're seeing
because it's not one thing it's funny
we're talking about this now and I'm
slowly starting to realize one of the
things I saw when I took
iwasa afterwards actually so the actual
ceremony is 4 five hours but afterwards
you're still riding whatever the thing
that you're riding and I got a chance to
um afterwards hang out with some friends
and just shoot the shit in the you know
in the forest
and I get to see their
faces and what was happening with their
faces and their hair is I would get this
interesting effect first of all
everything was beautiful and and I just
had so much love for everybody
but I could see their past selves like
behind them it was this effect where um
I guess it's a blurring effect of where
like if I move like this the faces that
were just there are still there and it
would just float like this these uh
behind them which will create this
incredible effect but it's also another
way to think about that is I'm
visualizing a little bit of that object
of the thing they wore just a few
seconds ago it's a cool little effect
very cool and now it's like uh giving it
a bit more profundity to to the effect
that was just beautiful aesthetically
but it's
also beautiful from from a physics
perspective because that is a past self
I get a little Glimpse at the past self
that they they were but then you take
that to its natural conclusion not just
a few seconds ago but just to the
beginning of the universe and you can
probably years get down that lineage
it's crazy that there's billions of
years inside all of us all of us yeah
and then we connect obviously not too uh
not too long ago yeah uh you you
mentioned the technosphere and you also
wrote that the most alive thing on this
planet is our technosphere yeah why is
the technology we create a kind of life
form why do you why are you seeing it as
life because it's creative but with us
obviously like not independently of us
and also because of this sort of lineage
view of life and I I think about life
often as a planetary scale phenomena
because that's sort of the natural
boundary for all of this causation
that's bundled in every object in our
biosphere
and so for me it's just sort of the
current boundary of how far life on our
planet has pushed into the things that
our universe can
generate and so it's the furthest thing
it's the biggest thing um and I think a
lot about the nature of Life across
different scales and so uh you know we
have cells inside of us that are alive
and we feel like we're alive but we
don't often think about the societies
that we're embedded in
as alive or a global scale organization
of us and our technology on the planet
as alive um but I think if you have this
uh deeper view into the nature of Life
uh which I think is necessary also to
solve the original life then you have to
include those things all of them you
have to simultaneously think about life
at every single scale the planetary and
the bacteria level yeah this is the hard
thing about solving the problem of life
I think is how many things you have to
integrate into building a sort of a a a
unified picture of this thing that we
want to call life and and a lot of our
theories of physics are built on um
building deep regularities that explain
a really broad class of phenomena and I
think we haven't really traditionally
thought about life that way uh but I
think to get it at some of these hardest
questions like looking for life on other
planets or the original life you really
have to think about it that way and so
most most of like my professional work
is just trying to understand like every
single thing on this planet that might
be an example of life which is pretty
much everything and then trying to
figure out like what's the deeper
structure underlying that yeah shinger
wrote that living matter while not
alluding the laws of physics as
established up to date is likely to
involve other laws of physics hether to
unknown so to him I love that quote
there was a
that at the bottom of this are new laws
of physics that could explain this thing
that we call Life yeah short really
tried to do what physicists try to do uh
which is explain things um and he his
attempt was to try to explain life in
terms of non-equilibrium physics because
he thought that was the best description
that we could generate at the time and
so he did come up with something really
ightful which was to predict the
structure of DNA as an AP periodic
Crystal um and that was for a very
precise Reas reason that you know that
was the only kind of physical structure
that could encode enough information to
actually specify a cell we knew some
things about genes but not about DNA and
its actual structure when he proposed
that but in the book he tried to explain
life is kind of going against entropy
and so some people have talked about it
as like Schrodinger's Paradox how can
life persist when the second law of
thermodynamic is there um but in open
systems that's not so problematic and
really the question is why can life
generate so much order and we don't have
a physics to describe that and it's
interesting you know generations of
physicists have thought about this
problem oftentimes it's like when people
are retiring they're like oh now I can
work on life uh or they're like more
senior in their career and they worked
on other more traditional problems and
there's still a lot of impetus um in the
physics Community to think that n
equilibrium physics will explain life
but I I think that's not the right
approach uh I don't think ultimately the
solution to what life is is there and I
don't really think entropy has much to
do with it unless it's entirely
reformulated well because you have to
explain how interesting order how
complexity emerges from the soup yes
from Randomness from Randomness physics
currently can't do that no physics
hardly even acknowledges that the
universe is random at its base
like to think we live in a deterministic
universe and everything's deterministic
but I think that's probably uh you know
an artifact of the way that we've
written down laws of physics since
Newton invented modern physics uh in his
conception of motion and gravity which
you know he he formulated laws that had
initial conditions and um fixed
dynamical laws and that's been sort of
become the standard Canon of how people
think the universe works and how we need
to describe any physical system is with
an initial condition and a law of motion
and I think that's not actually the way
the universe really works I think it's a
good approximation for the kind of
systems that physicists have studied so
far and I think it will radically fail
um in the long term at describing
reality at its more basal levels not I'm
not saying there's a base I don't think
that reality has a ground and I don't
think there's a theory of everything but
I think there are better theories and I
think there are more explanatory
theories and I think we can get to
Something that explains much more than
the current laws of physics do when you
say Theory of Everything you mean like
everything everything yeah yeah you know
like in in physics right now it's really
popular to talk about theories of
everything so string theory is supposed
to be a theory of everything because it
unifies quantum mechanics and gravity um
and you know people have their different
pet theories of everything and and the
challenge with a theory of everything I
really love this qu quote from David
crack hour which is a Theory of
Everything is a theory of everything
except those things that theorize oh you
meaning removing the Observer from the
thing yeah but it's also it's also weird
because if a theory of everything
explained everything it should also
explain the theory so the theory has to
be recursive and none of our theories of
physics are recursive so it's just a
it's a it's a weird concept yeah but
it's very difficult to integrate The
Observer into a theory I don't think so
I think you can build a theory
acknowledging that you're an observer
inside the universe but doesn't it
become recursive in that way and that's
you're saying it's possible to make a
Theory that's okay with that I think so
I mean I don't think there's always
going to be um the Paradox of another
meta level you could build on the The
Meta level right so like if you assume
this is your universe and you're the
Observer outside of it you have some
meta description of that universe but
then you need a metad description of you
describing that Universe right so uh you
know this is one of the biggest
challenges that we face um being
observers inside our universe and also
you know why the paradoxes and the
foundations of mathematics and any place
that we try to have observers in the
system or a system describing itself uh
show up um but I think it is possible to
build a physics that builds in those
things intrinsically without having them
be paradoxical or have holes in the
descriptions um and so one one place I
think about this quite a lot which I
think can give you sort of a more
concrete example is is the nature of
like what we call
fundamental so uh we typically Define
fundamental right now in terms of the
smallest indivisible units of matter so
again you have to have a definition of
what you think material is and matter is
but right now that you know what's
fundamental are Elementary particles um
and we think they're fundamental because
we can't break them apart further and
obviously we have theories like string
theory that if they're right would
replace the current description of
what's the most fundamental thing in our
universe by replacing with something
smaller um but we can't get to those
theories because we're technologically
Limited
and so if you if you look at this from a
historical perspective and you think
about explanations
changing as physical systems like us
learn more about the reality in which
they live we once considered Adams to be
the most fundamental thing um and you
know it literally comes from the word
indivisible and then we realized Adams
had substructure because we built better
technology which allowed us to quote
unquote see the world better and resolve
smaller features of it and then we built
even better technology which allowed us
to see even smaller structure and get
down to the standard model particles and
we think that there's might be structure
below that but we can't get there yet
with our technology so what's
fundamental the way we talk about it in
um current physics is not actually
fundamental it's the boundaries of what
we can observe in our universe what we
can see with our technology and so if
you want to build a theory that's about
us
and
about what what's inside the universe
that we can observe not what's at the
boundary of it um you need to talk about
objects that are in the universe that
you can actually break apart to smaller
things so I think the things that are
fundamental are actually the constructed
objects they're the ones that really
exist and you really understand their
properties because you know how the
universe constructed them because you
can actually take them apart you can
understand the intrinsic laws that built
them but the things at the boundary are
just at the boundary they're Evol in
with us and we'll learn more about that
structure as we go along but really if
we want to talk about what's fundamental
inside our universe we have to talk
about all these things that are
traditionally considered emergent but
really just structures in time that have
causal histories that constructed them
and um you know are really actually what
our universe is about so we should focus
on the construction methodology as the
fundamental thing do you think there's a
bottom to the the smallest possible
thing that makes something un I don't
see one and it'll take way too long
it'll take longer to find that than it
will to understand the mechanism that
created life I think so yeah I I think
for me the frontier in modern physics
where the new physics lies is not in
high energy particle physics it's not in
quantum gravity it's not in any of these
sort of traditionally sold this is going
to be the newest deepest Insight we have
into the nature reality it is going to
be in studying the problems of life and
intelligence and the things that are
sort of
also our current existential crisis as a
civilization or a culture that's going
through uh you know an existential
trauma of inventing technologies that we
don't understand right now the
existential trauma and the terror we
feel that that technology might somehow
destroy us us meaning living intelligent
living organisms yet we don't understand
what that even means well humans have
always been afraid of our Technologies
though right so it's kind of a
fascinating thing that every time we
invent something we don't understand it
takes us a little while to catch up with
it I think also in part humans kind of
love being afraid yeah we love being
traumatized it's weird we want to learn
more and then when we learn more it
traumatizes
us you know I never thought about it
this before but I think this one of the
reasons I love what I do is because it
traumatizes me all the time that sounds
really bad but what I mean is like I
love the shock of like realizing that
like coming to understand something in a
way that you never understood it before
uh I think
it seems to me when when I see a lot of
the ways other people react to new ideas
that they don't feel that way
intrinsically but for me that's like
that's why I do what I do I I love I
love that feeling but you're also
working on a topic where it's
fundamentally ego destroying CU you're
talking about like life it's humbling to
think that we're not the individual
human is not special yeah and you're
like very viscerally exploring that yeah
I'm trying to embody that uh because you
I think you have to live the physics to
understand it but uh there's a great
quote about Einstein I don't know if
this is true or not that he once said
that he could feel light beam in his
belly uh and I
think but I think like you got to think
about it though right like you're if
you're a really deep thinker and you're
really thinking about reality that
deeply and you are part of the reality
that you're trying to describe like you
feel it you really feel it that's what I
was saying about you always is like
walking along the cliff if you fall off
you're falling into madness yes it's a
constant constant descent in Madness the
fascinating thing about physicists and
Madness is that you don't know if you've
uh fallen off the cliff yeah I know you
don't know that's that's the cool thing
about I rely on other people to tell me
actually this is very funny cuz like I
have these conversations with my
students often like they're worried
about going crazy and I have to
like reassure them that like one of the
reasons they'll stay sane is by trying
to work on concrete problems
going crazy or waking up I don't know
which one which one it is yeah uh so
what do you think is the origin of life
on Earth and how can we talk about it in
a productive way the origin of life is
like this
boundary um that the Universe can only
cross if a structure that emerges can
reinforce its own existence which is
self- reproduction autocatalysis things
people traditionally talk about but it
has to be able to maintain its own
existence against this sort of
Randomness that happens in chemistry and
this Randomness that happens in the
quantum world and like it's in some
sense the emergence of like a
deterministic structure that says you
know I'm going to exist and I'm going to
keep going um but uh you know pinning
that down is really hard we have ways of
thinking about it in assembly theory
that I think are pretty rigorous and one
of the things I'm really excited about
is trying to actually quantify uh in an
assembly theoretic way when the original
life happens but the basic process I
have in mind is like a system that has
no causal contingency no constraints of
objects basically constraining the
existence of other objects or forming or
are allowing the existence of other
objects um and so that sounds very
abstract but like you can just think of
like a chemical reaction can't happen if
there's not a catalyst for example or a
baby can't be born if there wasn't a
parent um so there's a lot of causal
contingency that's necessary for certain
things to happen so um you think about
this sort of unconstrained random system
there's nothing that reinforces the
existence of other things so so the sort
of resources just get washed out in all
of these different structures and none
of them exist again um or they just you
know they're they're not very
complicated if they're in high abundance
and some random events allow some things
to start
reinforcing the existence of a small
subset of objects and if they can do
that um you know like just molecules
basically recognizing each other and
being able to catalyze certain
reactions uh there's this kind of uh
transition point that happens
where unless you get a self reinforcing
structure something that can maintain
its own existence it actually can't
cross this boundary to make any objects
in high abundance without having this
sort of past history that it's carrying
with us and maintaining the existence of
that past history and that boundary
point where objects can't exist unless
they have this selection and history in
them is what we call the original life
and pretty much everything beyond that
boundary um is holding on for dear life
to all of the causation and causal
structure that's basically put it there
um and it's carving its way through this
possibility space um into generating
more and more structure and that's when
you get the open-ended Cascade of
evolution but that boundary point is
really hard to cross and then what
happens when you cross that boundary
point and the way objects come into
existence is also like really
fascinating Dynamics because you know
like as Things become more complex the
assembly index increases I can explain
all these things sorry you can tell me
what you want to explain uh me to
explain or what people want will want to
hear um this uh sorry I have like a very
Vivid visual in my brain and it's really
hard to articulate it got to convert it
to language I know
so hard it's not it's like it's going
from like a feeling to a visual to
language is so stifling sometimes I have
to convert it yeah from language to to a
visual to a feeling yeah I think it's
working I hope so I really like the
self-reinforcing objects I
mean just so I understand one way to
create a lot of the same kind of object
is make them self
reinforcing yes so self- reproduction
has its property right like if a system
can make itself then it can it can
persist in time right cuz all objects
Decay they all have a finite lifetime so
if you're able to make a copy of
yourself before you die before the
second law eats you or whatever people
think happens um then that structure can
persist in time so that's a way to sort
of emerge out of a random soup out of
randomness of soup right but things that
can copy themselves are very rare yeah
um and so what ends up happening is that
you get structures that enable the
existence of other things and then
somehow only for some sets of objects
you get closed structures that are
self-reinforcing and allow that entire
structure to persist right so the one
object a reinforces the existence of
object B but you know object a can die
yeah so you have to like close that Loop
right so this is the class all very
unlikely statistically but you know
that's sufficiently um it's so you're
saying there's a chance there is a
probability and then but once you solve
that once you close the loop you can
create a lot of those objects and that's
what we're trying to figure out is what
are the causal constraints that close
the loop so there is this idea that's
been in the literature for a really long
time that was originally proposed by
Stuart Kaufman as really critical to the
origin life called autoc cic set so
autoc set is exactly this property we
have a makes b b makes c c makes a and
you get a closed system but the problem
with the theory of autoc cataly sets is
incredibly brittle as a theory and it
requires a lot of ad hoc assumptions
like you have to assume function you
have to say this thin