Hello, and welcome to the Physics World weekly
podcast.
I'm Hamish Johnston.
It's book week here at Physics World. And
over the course of three days, we're presenting
conversations with the authors of three fascinating and
fun books about physics.
Today, my guest is the physicist Daniel Whiteson,
who along with the artist Andy Warner
has created the delightful book, Do Aliens Speak
Physics?
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Is physics universal,
or is it shaped by human perspective?
This will be an important question if and
when we are visited
by an advanced alien civilization.
Would we recognize
our visitors alien science?
Or indeed, could a technologically
advanced civilization
have no science at all?
These questions and much more are addressed in
do aliens
speak physics?
And here to talk about his book is
Daniel Whiteson.
He's a particle physicist at the University of
California,
Irvine
from where he joins me. Hi, Daniel.
Welcome to the podcast.
Hi. Thanks very much for having me. I'm
so excited to talk about aliens with you.
Yeah. Well well well, so am I. I
really I really enjoyed,
reading your book. It was it was a
lot of fun. And and and I have
to say, you know, there's a lot of
really
fascinating
and, you know, dare I say, profound ideas
in there about,
I mean, maybe not so much about aliens,
but more about how we
perceive science,
today, and, you know, what science was like
in the past, and and what it could
be in the future. So,
yeah.
Dear reader, if you think this is only
about aliens, it's not. There's lots of, of
of really interesting stuff about
science and the philosophy of science.
Well, you really put your finger on it
actually because the book I originally wanted to
write was,
do we think about
physics in a way that's universal
or has our humanity somehow
injected itself into our science in a way
that's imperceptible to us? And I actually pitched
that idea to my 14 year old, who's
my Gage. And he was like, boring.
And so instead I said, all right, what
if it's a book about when aliens arrive,
could we talk to them about science? And
he was like, oh, that sounds like fun.
And I thought, cool. It's actually the same
book, but, you know, just in this sort
of more concrete
context where you're, like, faced with the task
of communicating with your interstellar
colleagues.
But, yeah, in the end, I really just
wanted to think and write about the nature
of science and what we've learned and how
much humanity is in it.
Yeah. That I mean, that's definitely what I
what I got out of it.
And, yeah, I I I really did enjoy
that sort of aspect of it. But let
let let's go for the first,
you know, the first sentence of the book.
I think you begin the book, imagine the
day
the aliens
arrive. And
I'm just I'm just curious.
Do you
I mean, do you think that one day
we will be
visited by
representatives
of an alien
civilization? Because, you know, you know, that's the
whole premise of the book. Mhmm. But is
that is that purely rhetorical?
Or,
you know, do you do you have an
inkling or or a wish for that to
happen?
I certainly do have a wish. I mean,
I've literally fantasized about that because
it feels to me like we are slowly
chipping away in the minds of truth trying
to understand how the universe works. And we've
been going at it for thousands of years,
and we've made some progress, but we also
have these hints that there's so much left
to understand, you know, dark matter, dark energy,
the expansion of the universe, cosmological
questions.
So it's frustrating to imagine that there could
be aliens out there that have spent a
billion years working on these projects. They could
just have the answers.
And the day they show up, if we
are working on the same questions and if
we can communicate, then they could leap us
forward into our scientific future and just tell
us these truths.
Wow. What an amazing day that would be.
I mean,
it's like seeing the face of God, you
know, or, you know, revealing the source code.
Wow. That would be amazing. So I definitely
wish that would happen and fantasize about it.
Whether I think it's likely to happen, you
know, that's
nonscientific
speculation, but, you know, there are many, many
planets out there
and around many, many stars, and the universe
is quite old, so there's a lot of
chances for it. On the other hand, you
know, we haven't seen anybody yet. And, of
course, there's the famous Fermi paradox about why
that might be. And my suspicion
is that,
aliens will arrive in the future. It's just
a question of time. You know, it's an
issue of overlapping for long enough
for somebody to develop the technology to explore
the galaxy. And
so I think it's important to sort of
mentally prepare ourselves.
What would it really be like when they
arrive? Are we ready for it? What work
do we need to do before they get
here to make sure we have a chance
to leap forward into our scientific future? And
it is, you know, it is interesting that
over the last thirty years,
you know, we went from knowing about zero
exoplanets,
that's planets that orbit stars other other than
the sun. Now we know that there's thousands
out there. Yeah. So, you know, in a
sense,
you know, maybe if you had asked me
that question thirty years ago, I would have
said no, maybe not. But now that I
know about all these exoplanets and the fact
that we're discovering more and more every day,
it it it it sort of hits home,
doesn't it? Quite literally that,
that that it is a possibility. And I
suppose that makes the Fermi paradox, you know,
the idea that,
if there are aliens out there, why why
don't we know about them?
Even more positive, isn't it? Yeah. It does.
And I think you're right. We're living in
a very exciting time to be thinking about
these questions because
for hundreds or thousands of years, we've known
about, you know, fewer than 10 planets in
the universe. Now we know 5,000.
We're looking on 10,000
soon.
And I think in the next few decades,
we're very likely to see,
you know, undisputable
hints of or or indisputable evidence
of life around,
other planets on around other stars. You know,
not direct imaging or visitation yet, but, you
know, biosignatures
in atmospheres,
we have the technology very soon to be
able to do that. I think it's likely
that will happen. And so we're living in
a moment when our understanding of who else
might be out there is really changing so
rapidly. And so it's very difficult to predict
what we're gonna know in a hundred years.
But, you know, the situation I'm imagining requires
much more than knowing there are aliens around
another star because
the difficulties of communicating with distant aliens
are really enormous. I mean, I spoke to
linguists and philosophers
who think it might be literally impossible to
decode an alien message
without some sort of common context, you know,
without them arriving here and us being able
to, like, point at an apple and say
apple and point at two apples and say
two apples and build up a dictionary.
I think at a distance, it would be
very, very difficult,
maybe impossible,
to actually figure out what they are saying.
You know, this symbolic language is very frustrating
and cultural.
So that's why I imagined aliens arriving on
Earth, because then we can maybe make some
progress and figure out, you know, do we
have mathematics in common? Can we begin and
from that and build up into an actual
linguistic communication?
I wanted to ask you about,
the extended Drake equation, which is something that's
central
to your book.
You know, it's I suppose it provides a
scaffolding
for Yeah. For you to hang a lot
of of your ideas and analysis on. Now
this extended Drake equation, is that something that
you came up with, or you and Andy
came up with? Because you you didn't come
up with the Drake equation. That's that's existed
for a while now. So is, I mean,
may maybe I could ask you to very
quickly explain what the Drake equation is,
and then maybe
the extended
Drake equation.
Yeah. Well, you already touched on the ideas
quite quite well, I thought. You know, a
lot of these questions,
are there aliens out there that we communicate
with? They have a lot of parts to
them. And in order for it to work,
in order for us to meet aliens or
hear from aliens, you need a lot of
things to all fall in place simultaneously.
You need enough stars. You need enough planets.
You need enough of those planets to have
life. You need enough of those to become
civilized. You need that all to happen at
the same time.
And the Drake equation
does two things wonderfully. I think it breaks
this big question into pieces that you can
think about individually, like,
what do we know about how many stars
have planets, etc?
And because it's multiplicative, it takes all of
these factors and multiplies them by each other,
it emphasizes
that you need all of them. I mean,
it doesn't matter how many stars there are
and how many planets there are If the
probability for life around a planet is one
over 10,
right, then the number is tiny. Or if
we are if it's one over, you know,
the number of planets in the universe because
we're alone.
Right? Any individual factor can kill you. So
I was thinking about that when I was
tackling this bigger question of not just are
there aliens out there, but are there aliens
out there that do science the way we
do and decided to break it down in
pieces? So the first piece we added to
the Drake equation, because we're looking for something
more specific than just aliens communicating, it's aliens
who we can talk to about physics. The
first piece was number one, do they even
do science, right? Could there be aliens out
there who are just, you know, slime on
planets or even aliens out there who are
technological
but not scientific,
who develop, you know, techniques to manipulate the
universe without wondering why, without having that same
human curiosity about how it works?
And then the second piece was, can we
communicate with them? Can we establish, like, a
mental bridge so we know we're talking about
the same stuff, and, you know, we could
even get their answers, you know, even if
they have some, like, deep understanding of quantum
gravity, could they communicate it to us?
And the next piece we thought about was
what about their questions? Would they ask the
same questions about the universe? Are our questions
human? Would they be curious
about different things? And then the last piece
are the answers.
In order to fulfill my fantasy where we
sit down and learn about what's inside black
holes and where the universe came from from
these super advanced aliens,
we also be have to be able to
appreciate their answers.
You know, I found when reading about the
philosophy of science and how science has evolved,
that there's a lot of subjectivity
in the answers that we accept, what we
find intuitive,
you know, and then there's also the question
of like, would we even be smart enough
to answer to hear their answers and understand
them? Wouldn't that be so frustrating to have
aliens show up, have them be friendly,
have them, you know, possess the knowledge of
how the universe works that we've been desperately
working towards and for us to just go,
I don't get it. Right? I mean, what
a sad trombone that would be the end
of that story. But the so to answer
your question about the extended Drake equation, this
is a way to break up this very
amorphous question into pieces
and and tackle them one by one. And
also to emphasize that for this fantasy to
come true, we really need all those things
to happen. They need to do science. We
need to be able to communicate with them.
We have to have questions and answers in
common with them. I see. And I I
wanted to start with the first one, which
is science.
And,
so
I think there in in the book, you're
you're sort of making a a distinction
between science and technology.
And I think right to begin with,
I suppose me with my physics background,
that gets me scratching my head because I
think, well, you know, how can you have
science
how can you have techno technology without science?
How can you have science
without technology?
But then I thought because I was talking
to somebody a
few days ago about thermodynamics,
and how, you know, thermodynamics
came about in the nineteenth century,
basically by people who wanted to make better
steam engines and pumps and things like that.
And so I thought, well, okay. Yeah. I
can sort of understand
in that situation
that the technology
led,
and maybe the science
came later.
But are are you saying that it it
could be that there are civilizations
out there where
there's only technology and no science?
I'm, you know,
I'm struggling with that, but I suppose your
point is that that could exist and that
could make it very difficult for us to
to
to understand,
such a civilization.
Yeah. You put your finger on it again.
I mean, the whole exercise of the book
is let's investigate our assumptions. It's very natural
for us to think, well, science is the
engine for discovering
the way the world works, which technology
requires. Right? But that's the way we've done
it. That's the way our civilization works. That
doesn't mean it's the only possible way, and
the book is basically an exercise in, like,
let's think about if we can imagine another
way. That doesn't mean that we're arguing it's
the best way or it's the only way,
but, like, let's explore the edges of the
sandbox and question our assumptions.
And we can't do that, of course, by
visiting aliens yet. But what we can do
is look back at the history of our
development and think about whether things could have
been different. And right away, when you look
back into our history, as you say, we've
been technological a lot longer than we've been
scientific. You know, people have been making incredible
swords,
improving on the technology to be sharp and
hard without understanding what's going on at the
microscopic level and the solid state physics. You
know, and there's lots of things that
universe today, technology that we have that we
don't fully understand. You know? Nobody knows how
Tylenol works. Right? Like,
it's amazing.
But we can develop technologies without understanding them.
The crucial thing, of course, is we want
to understand them. We have this innate curiosity.
To us, it's satisfying to know why. And,
of course, understanding it, building a mental model
of how it works lets you accelerate that
development.
But, you know, as I said, for a
long time, we were technological before we were
scientific. And so I thought about, you know,
is it possible to have a species that
is just technological?
And one thing we did in the book,
which I had a lot of fun with,
was come up with these hypothetical case studies
rather than just thinking about it abstractly. Is
it possible? I sat down to write these
little fictional narratives, you know, a couple of
pages
to imagine a scenario
which bends our assumptions. And so in this
case, I thought about how a civilization might
actually develop
an understanding
of general relativity
and the way space works is an intuitive
way, in a way that they just use
it and become familiar with it, and eventually
use it to travel the galaxy
so that they could even show up here
with effectively
wormhole or warp drive technology.
And we ask them, hey, how does that
work? And they're like, well, I can show
you how to do it. What do you
mean? How does it work? You know?
They might be technological
without being curious. It might be enough for
them to be like, well, here's how you
do it. You surf the curvature of space
time.
I'm not saying that's more likely, and of
course I'm not saying that we don't need
science to develop technology,
but, you know, if you have a lot
of time and incredible
variety in the universe, you might get all
sorts of weird aliens, and we should be
prepared for aliens who show up and don't
understand why we want to ask why about
the universe,
why it's not enough for us to just
do it and to use it, you know,
to wonder how those swords work and why
yeast ferments and how Tylenol works and all
these things. So a lot of this book
is about asking how much we have in
common with aliens. And this part, this curiosity,
this desire to understand,
boy, that's, you know, subjective. It feels very
cultural.
And, you know, also, if you if you
look back at just the history of science,
people have this conception that science came together
as empiricism
on top of, you know, just platonic thinking.
A few hundred years ago when Galileo and
Bacon, you know, were inspired to do experiments
and to actually, you know, confront ideas,
with with data.
But the truth is a little bit more
subtle than that. You know, science is a
process that's been evolving for a long time.
The Greeks did some experiments and, you know,
the Arab scholars did experiments,
and the Chinese did experiments. And so it's
not just like a eureka moment where we
develop science itself, and now we have this
process which is fixed. It's growing and evolving.
It's
it's, hard to imagine that in a thousand
years, our own conception of the process of
science would be exactly the same. Probably it's
going to keep changing. And so
when aliens show up, if they've been doing
this for a billion years, they may either
have no idea what science is and not
care about it, or they could have some
super far in the future developed version of
science as a process. And they look back
on our science, they're like, y'all are kind
of primitive. Like, how come you didn't consider
this other way to develop knowledge about the
universe?
And so the first chapter is just to,
like, get you warmed up to think about
how aliens could really approach a lot of
these questions of science and technology very differently
than we might.
And,
so moving on to communication, I mean, I
suppose there again,
you, you know, you've got,
I suppose different ways. I've you know, I
think in the book you point out very
nicely that humans have used,
you know, sort of a wide range of
of, well, languages and and ways of writing
that, you know, even,
I suppose the classic example that you give
are the Egyptian
hieroglyphics
where,
you know, for a very long time, I
think thousands of years,
scholars were trying to interpret them
in the wrong way.
You know, sort
of weirdly sort of thinking that the Egyptians
didn't communicate like we did. Obviously, it was
something completely different and and and completely missing
the point until the,
I suppose, the Rosetta Stone
turned up and, and set people straight.
So,
I mean, one sort of idea that I
think you introduce
is
the question of
whether
physics
or maybe mathematics
or maybe
computer science
could
form the basis
of, I don't know, a universal
language or a universal
translator that Mhmm. Could we could go from
our way of communicating
into, let's say, physics and then
out to,
the alien
way of communicating. Is that can can you
talk a bit about that? Because I found
that really fascinating. And it sort of made
sense to me
when
when I I sort of gave up some
of your ideas about how
maybe physics is very different. And,
but yeah,
I thought it was
a very interesting concept. Can you talk about
that a bit?
Yeah, I think a lot of people imagine
that, you know, when aliens arrive, obviously they
won't speak English. That'd be ridiculous.
And they might use some weird sort of,
language or communicate with their senses, with their
sense or with colors or whatever.
But that at the foundation,
we have math and physics in common. And,
you know, Carl Sagan has a famous quotation
about this, and he designed the pioneer plaque,
which describes some basics of, you know, hydrogen
and our representation of the solar system. And
it's all, you know, pictograms. It's obviously not
using words. And I think, you know, the
inspiration
is, is, is right there. It's a way
of saying, like, let's try to describe some
core basic concepts that maybe we have in
common.
But, you know, in the end, all of
these things are symbols.
All of our attempts to transmit an idea
from one brain to the other have to
pass through this
symbolic representation where we
scratch images onto a surface and pass them
to somebody or encode them in data and
pass them pass them on. And that encoding,
that translation into symbols is totally arbitrary. You
could pick any symbols you want. And so
to imagine that aliens are gonna, like, look
at the pioneer flag and go, oh, yeah.
I can tell you met hydrogen atom. And,
oh, yeah. I see what you mean. This
must be a pulsar.
It's hopeful, but a little bit naive maybe.
And so I was thinking, you know, what
could we rely on? What way could we
use to try to establish connections with aliens?
And so I actually called up Noam Chomsky
because he famously answers his emails and asked
him. I thought, you know, who else better
to ask about
communicating,
with aliens and the foundations of language? That's
the the famous linguist,
Noam Chomsky. Yeah.
And, you know, he said we should begin
with arithmetic. He said arithmetic is very likely
to be something we have in common. And
he had a reasonable argument for that. You
know, he imagined,
that aliens probably count themselves.
You know, they are individuals.
And so there's one alien, two aliens, they
learn, you know, counting. And from that you
build arithmetic and,
he and Marvin Minsky together have this argument
about how from arithmetic, you can build up
essentially all of language
that from arithmetic, you get all of math
because we've learned the last few hundred years
that
all of math rests on arithmetic, which is
based on these PNO axioms, which are the
foundation of all of mathematics.
And so basically once you have arithmetic, you
can build up all of math. So imagine
a scenario where aliens show up and we
establish one and two and one plus one
equals two etc etc
and from there we can build, most of
mathematics and from there we can communicate perhaps
in the language of computers writing programs
essentially
as Turing machines. Turing machines are the simplest
possible computer that you could build.
Not that you have to build them in
this silly way with tapes and and and
and rulers etcetera, but just as an argument
for what computers can do.
That from arithmetic, you can get to mathematics,
and then you can get to algorithms, and
then you can use algorithms as the foundation
of a way to communicate with an alien
species. You know, essentially moving information around, writing
a program to do something
as a way to communicate this is what
we want or this is how we do
this calculation.
And that's very attractive, but still at the
foundation of it
are some assumptions. You know, how do we
know that aliens
have individuals
that they count? What about aliens that are
like beings in the atmosphere of a star
and they're made of plasma and the edges
of their bodies are not so crisp?
If you dig into it, it's not even
easy to understand where is the edge of
me. I mean, you have this concept of
yourself as an individual and you and I
are different people. But, you know, if we're
in the same room, where exactly would we
draw the line and say, this is Daniel,
this is not Daniel. Is it at the
edge of my skin? Is it the little
hairs that perturb? Is it my personal space?
Very quickly, you find the philosophy there is
somewhat cultural and arbitrary.
And if we had a different kind of
body,
ones that were more flowy and less less
crisp, we might never come up with the
concept of integers. You know, it might all
be,
real numbers. And so start trying to start
with one and, and one and two might
get us off in on the wrong foot.
So everywhere you go, there are these philosophical
assumptions we're making, these cultural assumptions we're making
about how to communicate and what's really at
the foundation.
But it's a lot of fun to dig
into these things and to wonder about various
scenarios
where aliens might arrive and and the difficulties
we might face with communicating with them. Yeah.
Because one one thing that, you know, I
I thought, you know, from the point of
view of physics is I I I think
you allude to this in the book somewhere
about,
an alien civilization
seeing,
you know, the Earth as a
as a system in the same way that
we would see, I don't know, the electrons
in a semiconductor
Mhmm. As a system.
And so, you know,
humans would be,
well, I suppose from our point of view
would be sort of an an emergent
phenomenon
within
that system.
And, you know, would they necessarily
see us
or perceive us
as individuals, or
would, you know, would they be you know,
would would we be sort of like quasi
particles to them?
You know, things that that that sort of
exist, but
really
are are completely
dependent on
the environment, which I suppose we are,
you know, to a certain extent. We are
quasi particles
within Earth because we we couldn't exist, you
know, in the same way that,
I don't know, phonon doesn't exist in, in
a vacuum. We wouldn't exist in space for
very long. It you know, I
I I suppose those were the the sort
of thoughts
that I was having when I read the
book.
And, you know, I I, you know, it
was real it was
I suppose it just made me think
in a in a very different way,
about what it means to be human.
Yeah. That was something that I didn't expect
to get from the book, I suppose.
Yeah. Well, this is a really fun topic
and and one that's so fascinating and mysterious.
This question of, you know, why things emerge.
You know, as you say, we are emergent
phenomena. We're not fundamental to the universe. There
was a time before there were humans. There
may be a time after there were humans.
We're not necessary. We're like this special combination
of particles
that do this thing when they're all together.
It's like ice cream or kittens. Right? It's
not,
fundamental fields or strings or whatever, and that's
obvious. But the thing that's fascinating is that
you can sort of zoom out from the
microscopic details of the universe and think about
people and build from that an understanding of
society and psychology and economics,
the way you can, like, zoom out from
particle physics and do chemistry and think about
atoms. Even though atoms are not the fundamental
building block of the universe, it's possible to
tell fairly simple, fairly understandable stories about chemistry
or to zoom out to biology and think
about ecosystems. And it's amazing to me that
the universe
is understandable
at all these different levels of zoom.
It's not obvious to me why that even
is, you know, why can you make chicken
soup or understand humans without knowing quantum gravity?
You know, I can imagine a universe where
that's not possible at all, where everything is
just chaotic from the fundamental level and nothing
simple emerges.
And because we don't know why simplicity emerges
and why at these levels,
then we can't be sure
that it is emerging, that it's a property
of the universe. It's not some bias that
we have where we're seeing it in some
way because that's what's important to us. You
know, the famous experiment where you watch a
video of a basketball game and they tell
you to count the number of passes and
you don't notice that there's like an ape
walking through the background. And Right. Yeah. What
you perceive and what you see and what
you ask questions about in the universe depends
very much on what you're interested in and
what's important to you.
And so it may be that our, you
know, the fact that we grew up on
a planet, for example,
makes us preordained to think about planets and
to think planets are really important in the
universe.
And maybe that's not. Maybe planets are trivial
and not interesting and other aliens could think
about the universe in terms of different foundations.
So if you look at the way we
represent the solar system, for example,
planets are, like, always out of scale. We,
like, zoom them out way out of scale,
And we don't even have, like, a good
definition for what is a planet, right? We
have this very awkward
sort of, you know, the retcon definition to
make planets an interesting and special thing because
we grew up on one. But, you know,
aliens
who again grew up in interstellar space or
the atmosphere of a star or inside a
star or on a moon or, or something
might have a very different sense of what's
foundational, what's important. And
they could see different, I don't know, layers
of Zoom, see different things emerge and and
use that as the basis of their questions
and of their science. And so, yeah, they
might not even recognize that humans
are what we consider to be the foundational
element of our society. They could think of
groups of humans or, you know, parts of
us.
And and again, not to say this is
the most likely, but it's just an exercise
in questioning our assumptions and wondering
where our humanity is biasing our perspective.
So so if we assume that we can
we can have some sort of communication with
an alien civilization,
we we sort of move on to the,
I suppose, the questions.
Yeah. You know, human human scientists
scientists
ask
certain questions of nature,
and you know, I suppose you've pointed out
that those questions are probably very biased
Mhmm. In terms of our environment.
What, I mean, what are the possibilities for
the sort of questions
that,
an alien civilization
could ask?
And, you know, would the answers to those
questions even be meaningful to us?
Yeah. Well, one way to start to think
about that is to think about
You
know, what universe are they
perceiving? Right? We have a certain
set of senses about how the universe, it
says that our senses that give us a
window to the universe,
They may have a different set of senses
or it could be very similar.
You know, we know for example, that most
of the universe is invisible to us, neutrinos
and dark matter and dark energy. None of
this is something we can register directly.
We, of course, can build technology,
which senses it and translates it into something
we can sense scribbles on the computer screen,
but we can't immediately
understand it.
And I think this definitely shapes the kinds
of questions we ask about the universe, you
know, what's out
there. And what's interesting to study. We spend
most of our time thinking about the 5%
of the universe that we can directly interact
with,
but also
it changes the way we get those answers
and the answers that we find intuitive.
You know, think about how we ask and
answer questions about quantum mechanics.
We tend to talk about these quantum objects
in analogy to things we find intuitive, to
things we can sense. So we talk about
the photon and we describe we compare it
to waves in the in water. We compare
it to tiny bits of rock, you know,
essentially mini particles.
And we know that neither of those are
correct. The photon is neither a particle nor
a wave. And, you know, there's lots of
confusing popular science about how it's both and
sometimes or whatever. But the reality is it's
neither. It's something new and weird that can
only be partially described by our intuition.
And so in that sense, we're fundamentally limited
from deeply understanding
what is a photon because we're coming at
it from these intuitive concepts that are based
on the way we perceive the universe. And
so imagine aliens that are like really microscopic.
So for them, quantum phenomena
are not a bizarre recent discovery, but something
they find intuitive.
Maybe they can interact with quantum objects without
collapsing them. And so they can like per
perceive superposition
to them. The quantum objects are intuitive
and so, you know, the kind of questions
they would ask could be different, but most
importantly the kind of answers they find intuitive
and
and the answers they accept could be very,
very different,
because to them these things are intuitive. In
the end, we're always translating
our explanations for the universe back into the
concepts we find intuitive, which are shaped by
our senses, which affect the way that we
think. And so, you know, what is it
like to be an alien
that can taste electrons and experience photons and
and to think about the quantum universe in
that way? It's it's hard for me to
even put myself in that in the mind
of that kind of creature. But I think
it's important to recognize that they could be
inspired to ask different questions about the universe.
Maybe they're not so interested in drilling down
and to understand the fundamental nature of the
universe. Maybe they figured out that there is
no fundamental nature. Maybe it's all just layers
of emergence.
And the answers that they find acceptable, you
know, we struggle with photons, but they might
be like, yeah, okay, it's just like that,
and move on, you know?
And and do you think, you know, let's
say, for example, we were able to communicate
with,
let's say, this micro microscopic,
civilization that
exists in a quantum world.
I mean, do you,
you know, there's the the the possibility that
we could learn
a lot from them
about quantum mechanics. And
they might be oblivious to a lot of
things in the in the classical world. Mhmm.
I mean, do you do you think that
there could be a meaningful
exchange
of knowledge between
two such civilizations,
or
will
they always exist
in solitude
just because,
you know,
the the the the meaning of things is
so different
in each, you know, it's almost like two
different
universes.
Yeah.
No. I think there's a lot that we
could learn and a lot of information we
could exchange. And I really hope that when
the aliens arrive, even if they're super advanced,
that we do have some nuggets that we
worked out that they find fascinating and useful.
But I think that regardless, we'll learn something.
I mean, imagine aliens arrive, microscopic or not,
they might just have a very different set
of answers to how the universe works. You
know, we have a theory of the universe,
and it's very, very effective. It's so precise
and accurate that it makes people feel like,
Wow, this is like the source code of
the universe. It must be true. But we
really have no guarantee that it's true, and
specifically in the sense that there could be
a second theory. You know, philosophers of science
debate this endlessly, whether there could be multiple
independent,
conceptually
different, but both simultaneously
effective theories of the universe. And when I
first read about this, I thought, no, that's
impossible.
If you have two theories that are making
the same predictions,
they must be fundamentally equivalent at some level,
and this is sort of an open question
in philosophy of science,
but it might be that aliens show up
and, you know, we have a theory of
quantum fields and they have a theory of
schwontum fields or something, you know, some
categorically
different
story about what's happening
in the universe because in the end our
theories of the universe are theories about the
invisible.
They are talking about what's going on behind
the scenes to explain what we do see.
You know, for example, nobody's ever seen a
field. We only see fields when they affect
things we can see. Like, we talk about
electric fields, but really it's an intermediate calculation
in our minds to explain what happens to
an electron.
Right? The field is never observed directly. So
is that a real thing, or is that
a fiction in our minds?
So when aliens show up, if they have
a completely unique
description for how the universe works totally different
conceptually from ours,
we will still learn something.
Even if they don't improve our knowledge, we
can look at theirs and compare and say,
Oh, this is interesting. These parts are similar,
but this is very different.
So no matter what happens, we'll learn something
about how human, how arbitrary our theories are.
And if they show up and they are
doing quantum field theory and string theory, that'll
also tell us a lot like, wow, maybe
this is true. Maybe this is fundamental. Maybe
this is this is universal
beyond just the human scope. So I think
we're guaranteed to learn something either way.
I see. Well, that's great. I mean, that
I suppose that brings us to the end
of the
extended
Drake equation.
I I wanted to ask you about,
your collaborator,
Andy Warner, who's who's done some fantastic
cartoons
that, I think there's there's at least one
on every page, isn't there? Yeah.
At least in the in the PDF version
that I have. And we were chatting before
this interview, and you said that
Andy doesn't have a physics background. Is that
right?
That's right. He's an artist, but he also
knows a lot about the history of science.
I've, been following his cartoons online for years.
He does fantastic,
nonfiction cartoons. He's written really fun books, you
know, like the history of ordinary objects, everyday
objects.
And I really enjoyed his style and his
humor. And so one day I just cold
emailed him and said, hey, do you wanna
collaborate on a book about aliens?
And we started chatting and explained to him
the idea.
And then I realized not only could he
add a lot of really fantastic visuals because
I think it's really helpful to, you know,
see what these aliens might look like, but
he also knew a lot about the history
of science and was into the philosophy.
So, yeah, he doesn't just illustrate the book.
He also took all of my writing and
made it under more understandable and added lots
of details to it and history.
We had a great time working together on
this book. It was it was a pleasure
working with Andy. Oh, that's great. And I
suppose another
another thing I'd I'd like to ask you
about I know I know this is a
bit of a downer, but,
you know, there there is a school of
thought that,
an alien encounter
could be a complete
disaster.
You know, it's a sort of colonial,
idea. It's you know, go ask,
the indigenous people of The Americas how great
it was when the Europeans turned up, that
that sort of thing. Are you,
does that
worry you? I mean, I suppose in a
sense there's nothing you can do about it.
But,
do you see different degrees of encounter?
Mhmm. Some being very positive and others, well,
maybe being a disaster. I mean, I think
there is a a cartoon right at the
beginning, isn't there? Where you address that. You
and Andy address that in the book.
Yeah. We we have no idea what aliens
would do if they show up. Up. You
know, are they gonna nuke us from space?
Are they gonna enslave us or eat us
or drop wisdom bombs on us? We really
have no idea,
what they might do. I'm a big reader
of science fiction, and obviously this is all
just speculation.
But to me, it seems strange to imagine
aliens would come and, like, try to take
over the Earth or whatever. It's not like
the Earth has special resources.
You know, you want water? There's, like, planets
filled with water in the outer solar system.
Help yourself.
You know, you want heavy metals? The asteroid
belt is filled with platinum and gold and
whatever.
The only thing that's really interesting about the
Earth is the life here and the intelligence
here. And so, like, yeah, come talk to
us.
It's hard to imagine, but, you know, I
just written a whole book about how we
shouldn't base our assumptions. We shouldn't make assumptions
about what aliens might do or think or
want.
So there obviously is the potential for great
danger there. Civilization
is at stake.
But, you know, I am so curious about
what aliens might be thinking about the universe
and if we could learn from them that
personally,
I would take the risk. Like, if there's
an alien ship zipping by the solar system,
we have the option of whether to let
them know we're here. I'm saying yes. Let's
hit that red button and let's gamble it
because we would learn so much
about life and the universe and ourselves
by talking to alien scientists. I I wouldn't
wanna pass up the opportunity.
And and what about,
you know, this idea of trying to communicate,
with aliens, you know, in the sense of,
sending out messages,
you mentioned the sort of Carl Sagan and
and is it Frank Drake Frank Drake,
messages that were sent out on,
is it Pioneer and and Voyager?
Is that, I mean, is that something
that we should be doing? Is it,
you know, could it work or is it
futile? The distances are so great.
I think it's worth doing, but obviously I
shouldn't speak for humanity and it's a complicated
question. I know the folks at SETI have
spent a lot of time thinking carefully about
this. I spoke to Jill Tartar about this
and building a consensus on the Earth from
all different cultures and backgrounds about whether or
not this is the right thing to do
is a challenge, and that's the right way
to do it. You know, like one flipping
physicist who's curious about the universe should not
be determining the fate of the planet.
We should be careful and thoughtful about that.
And I know people send messages into space
without necessarily,
you know, coming to a consensus.
But personally, I think it's unlikely
that we are going
to receive a message that we understand. For
that to happen, you know, we have to
anticipate
the technology they use, the encoding they use,
reverse engineer it when we have no idea
what the message is supposed to look like?
That's very, very difficult. Mhmm. As we were
talking about earlier in the podcast, like, even
breaking down human languages
is challenging and almost impossible, and we weren't
able to do it for hieroglyphics without the
Rosetta Stone. And even still, it took twenty
years, and there are existing human languages we
have not been able to decode. So the
idea that we could get, like, a a
snippet of alien language and somehow be able
to figure out what it says seems very
unlikely to me,
which is why in the book, again, I
focused on aliens arriving because then we have,
like, a physical context from which to build
up potentially some kind of communication.
But so personally, I say yes. Let's broadcast
to the universe because I wanna start the
first inter stellar science conference. But I acknowledge
there are risks there, and everybody's read the
Dark Forest trilogy knows all about them, and
my voice definitely shouldn't be the loudest. But
for me, the curiosity about the universe is
paramount.
Well, that's great. That's, that's a good place
to leave it, Daniel.
So that's, that's your book,
Do Aliens
Speak Physics,
and, that's cowritten with, Andy Warner. And I'll
put a link,
to the book in the notes for this
podcast.
Thanks very much for the conversation.
Always wonderful to talk about aliens with interested
folks. Great. Thanks for coming on the podcast,
Daniel.
That was Daniel Whiteson of the University of
California,
Irvine.
He's cowritten,
Do Aliens Speak Physics? With the California based
artist, Andy Warner.
Their book is published by w w
Norton and Company,
and I'll put a link to it in
the podcast notes.
Thanks to Daniel for joining me today
and to our producer, Fred Isles.
Thank you for listening to this podcast, which
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