Nuclear war, outofcontrol artificial
intelligence, planet decimating
pandemics, asteroid strikes,
superpowered gammaray bursts. There are
many ways humanity could meet its end,
and philosopher Nick Bostonramm has been
trying to list them all.
Bostonramm spends most nights alone in
his office, working obsessively until
the early morning. When he does sleep,
he uses a bed near his desk. He almost
always seems concerned and maybe with
good reason, for he has found one
particular threat to humanity that is
seemingly unavoidable.
In 2003, Bostonramm wrote a provocative
paper with a potentially dire outlook
for the human race that stated that
either we all live in a simulation or
we're all doomed. The argument goes like
this.
To begin with, assume that intelligence
and consciousness don't require a
biological brain. That it might be
possible to create a machine
intelligence with hardware and silicon
rather than neurons and sodium ions.
Assume also that as time goes on, our
computing prowess grows ever more
sophisticated and that someday, far into
the future, we could build a computer so
powerful that it is capable of
simulating the entire universe up to and
including the appearance of digital
beings that are fully conscious,
curious, and aware of their
surroundings, but completely unaware
that they live in a digital recreation.
How many digital beings would exist? The
number could be enormous.
Today, there are roughly 8 billion
people on Earth, which represents
roughly 7% of all the humans that have
ever lived since we first arose to
consciousness 200,000 years ago. But
compare that to the trillions upon
trillions of digital creations that we
have made in only half a century. And so
once some intelligent species somewhere
in the universe, whether us or somebody
else, successfully builds a digital
recreation of the cosmos,
argues there's no turning back. The
number of simulated conscious beings
will inevitably dwarf the number of
organic brains. And by sheer weight of
numbers, the chances that we are a
simulation become nearly a certainty.
If it's possible to simulate the
universe, the odds say that we should be
living in a simulation.
That is, unless there's something
preventing the appearance of simulated
beings.
Boston argued that there was another
possibility, a way out of the inevitable
conclusion that we almost certainly live
in a simulation.
It could be impossible to build
simulated universes with simulated
brains because no civilization becomes
advanced enough to accomplish it. That
all intelligent species reduce
themselves to ashes once they harness
the energies and technologies capable of
such a feat. In other words, we can rest
assured that we are definitely not
simulated if the end of our species is
right around the corner. And so if we
could conclusively determine whether or
not we live in a simulation, then we
could know what fate is in store for
humanity.
But how could we do this? Is there a way
to figure out whether we live in a
simulation or not? Is there a way to
save the human race?
for supporting educational content on YouTube.
How much information would you need to
simulate the entire universe?
The summit of Sero Pachchon in the dry
high altitude Kimbo region of northern
Chile is a lonely place. It's surrounded
by a vast desert with what little scrub
and succulents there are largely
supported by occasional mists that blow
in from the coast. Some animals make a
meager living here, hunted by foxes and
migratory birds. And yet, this isolated
mountain serves as humanity's focal
point in its attempts to peer into the
cosmos.
The Vera C. Rubin Observatory is not a
normal telescope. At its heart sits a
digital camera the size of a car with a
resolution of 3,200 megapixels. And
every single night, the telescope scans
nearly the entire southern sky,
producing roughly 20 terabytes of data.
This is so much that astronomers had to
build an entire dedicated digital
infrastructure to pipe the data down
from the mountaintop to a processing
facility in Lasserena, almost 100 km
away. Indeed, during its planned 10-year
mission, it will accumulate a total of
500 pabytes of data, equivalent to every
single thing written by every single
human in all of history. It will map
over 17 billion stars in the Milky Way
and 20 billion galaxies in the local
universe. And it will do it again and
again and again, night after night,
providing an unprecedented time lapse of
all the activity in the heavens.
However, the Vera Rubin Observatory will
barely scratch the surface of the sky.
Its catalog of stars will represent less
than 5% of all the stars in our galaxy.
Its catalog of galaxies, the largest
we've ever produced, will still be less
than 1% of all the galaxies in the
observable universe. For every supernova
it records, it will miss thousands. And
this is a pattern repeated across
telescopes and experiments throughout
all of human history. We've barely
scratched the surface of the cosmos. All
93 billion lightyears across we have
access to and all 10 to the power of 88
particles it contains. Indeed, in a 2009
paper, physicists Charles Egan and
Charles Linewaver calculated that our
universe has a total information content
of roughly 10 to the power of 122 bits.
A single star has 10 ^ of 59. A gram of
water 10 ^ of 24. A rough estimate of
all the data contained by all the
computers and all the servers on Earth
comes in at roughly 200 zetabytes. That
is also 10 to the^ of 24. The universe
is very big. And even that is just the
observable universe. the only part of
the cosmos that we could ever access or
have any causal contact with due to the
limited speed of light in the 13.8
billion years since it began. Beyond
that boundary, who knows? It could be
infinite.
And yet, despite the relative pority of
information, we have learned much.
We can trace the history of the universe
all the way back to some of the earliest
moments of the big bang. We can
reconstruct the formation of the solar
system and the lineage of life on Earth.
We understand the mechanisms of the cell
and the interaction of its molecules. We
have traced the rules of quantum
mechanics and the subatomic world. And
so if we had the capacity, do we know
enough about how the universe works to
simulate everything in it?
And so perhaps here lies the key. We
have to work out if it's possible to
create a onetoone simulation of our
universe and hopefully through that
process discover whether Boston's fears
are founded or if humanity can be saved.
Let's start with the cosmic and work our
way down.
One of the preeminent software tools for
simulating the entire universe at least
at large scales is called a repo. First
released in 2019, it continues to be
updated and maintained today. The code
starts by dividing up a portion of the
universe volume of up to a few billion
lightyears on a side into a large number
of individual cells. For the very
largest simulations, individual cells
can be much smaller than galaxies, but
this requires using some of the largest,
most powerful computers on the planet.
Each cell keeps track of what the
universe is like inside its volume. How
much dark matter there is, how much
regular gas, the temperature and
pressure of that gas, any magnetic or
electric fields, the state of any
radiation, and so on. It's as if you
took a chunk of a galaxy, smoothed it
over, and described that chunk by its
averages. The code can also estimate how
many stars are inside that cell, if
there are any supernova occurring, and
if giant black holes happen to be
belching out matter and radiation given
a state of the universe, the code can
then leap forward in time using all the
appropriate laws of physics to figure
out what happens in the intervening
millions of years. Dark matter shuttling
around due to its gravity, gas
collapsing and igniting into stars,
galaxies approaching each other and
merging together. And a repo adapts,
automatically assigning more and smaller
subdivisions in the complex parts and
freeing up memory in the empty parts.
But for all their impressive power,
cosmological simulations cannot
simultaneously capture both the
evolution of the universe and for
example the dynamics of a single planet.
For that we must turn to another kind of
simulation.
On August the 13th, 1958, a team of
physicists and meteorologists at the
University of Chicago created the first
hurricane crystal ball. At the time,
tropical storm Becky had formed in the
Mid-Atlantic and was steadily marching
westwards to the Americas. The team used
digitalized data of the storm's current
status, its wind speeds, and pressure
readings throughout its volume. They
then fed this into a physical model that
predicted how the storm would advance.
And in doing so, they created the first
ever computerized hurricane prediction.
And today, government agencies around
the world employ dozens of monitoring
satellites to provide realtime data,
which feeds into giant computer
simulations that run around the clock.
This means that when a large storm
approaches, we can finally speak with
remarkable confidence about its future
track, guided by our simulations of the
future of the world.
But yet again, these powerful
simulations and exquisite predictions
still have their limitations.
Their view of a major storm is limited
to a resolution of around 1 to 2 km.
Below that, they must average it out. In
other words, they can't follow or
predict individual raindrops or the
molecules inside the drops themselves.
To do that takes yet another kind of
simulation, one powered by PlayStations.
It is 3 minutes 3 on the 23rd of
September, 1992 at the Nevada test site
in the southern United States, and all
is eerily silent.
The hot sun beams down on the cracked
desert ground as a collection of small
white buildings absorb and reflect its
brutal midday glare.
Then, suddenly, as the clock ticks over
1 second to form its past 3, the ground
itself begins to violently shake.
Something has exploded deep below for
the last time. This was the divider
nuclear test carried out by the Los
Alamos laboratory 47 years after they
carried out the very first, the 154th
nuclear test carried out by the United
States. It would be the last by either
the US or the Soviet Union before the
signing of the nuclear testban treaty in
1996.
And indeed, ever since that nuclear
testban treaty, the United States has
not directly tested any of the weapons
in its nuclear arsenal. And so, how
could it ensure the reliability and
performance of those bombs should the
need arise?
The answer, simulate their inner
workings as they lie in storage.
This has made the US Department of
Energy one of the biggest proponents of
largecale supercomputers. And yet the
road to the most powerful computer in
the world had an unlikely way point. In
2010, the US Air Force Research
Laboratory wanted to build a new
supercomput of their own. And looking
around for vendors to supply the chips
for the computer, they realized that was
already a commercially available option.
In 2006, Sony had released the
PlayStation 3. They had collaborated
with IBM to create the cell chip, a
powerful microprocessor. And it turned
out that the kinds of computations that
the cell chip excelled at were very
similar to the kinds of calculations
that the Air Force needed. And so in
2010, researchers with the Air Force
plugged together a,760
PlayStation 3 consoles and got them to
work together, creating the Condor
Cluster, using that machinery to process
highresolution satellite imagery for
only a tenth of the cost of a typical
supercomput.
Today, our simulations of various
physical processes span almost the
entire breadth of physical existence.
They can take us from the earliest
moments of the Big Bang to the present
day. But to go even deeper into the
bedrock of reality, we must cross into a
completely different realm. We must
cross into the quantum world.
Could we find computational clues hiding
in the fabric of the universe?
If we were to go looking for the
fingerprints of a creator or a systems
architect, we might not find them in
ancient texts or burning bushes, but in
the very constraints of physics. Every
programmer knows that even the most
powerful hardware has a budget. You
can't render an infinite amount of
detail at an infinite speed. the system
would crash. And indeed, when we look at
our universe, we see analogies to
precisely these kinds of optimization
tricks. Take to begin with the speed of
light. To us, 299,792,458
m/s feels like the cosmic speed limit, a
barrier that nothing can cross. But in
the language of computation, the speed
of light begins to look a lot less like
a law of physics and more like a global
clock speed. After all, it is the
maximum rate at which information can be
updated from one cell of the universe to
the next. If the supposed simulation is
to remain coherent, no signal can travel
faster than the hardware can refresh the
frame. Then there's the finetuning
problem. Why is our universe so
perfectly calibrated for life? If the
strength of gravity or the mass of an
electron were even slightly different,
stars wouldn't form and we wouldn't
exist. To the devout, this might suggest
a benevolent creator. But to a
programmer, it suggests parameter
tuning. The simulation that we lived in
might be version 1 million1, one of the
few successful runs where the variables
were balanced just right to see what
intelligence would do.
And finally, there is the plank scale to
consider as we zoom into the fabric of
reality. We eventually reach a point
where the smooth curves of space and
time break down into tangled mess. And
so some theories of physics like loop
quantum gravity envision spacetime as
discrete almost pixelated chunks. Just
as a digital image dissolves into
squares when you lean in too close. The
entire universe could have a minimum
resolution.
And so perhaps what we see as inviable
constraints on physical reality are just
system settings designed to maintain
efficiency. Maybe the universe is trying
to save on memory. Indeed, by only
rendering the subatomic world when
somebody is looking at it, the hallmark
of quantum mechanics, the computer that
runs the universe, could save massive
amounts of processing power.
But other than that, quantum mechanics
would perhaps be the biggest obstacle
one would face when creating a one-toone
simulation of our universe. A seemingly
completely unpredictable subatomic realm
where objects can be in two places at
once, and nothing is ever truly certain.
Even the most modern computer would
collapse, attempting to recreate its
various intricacies, and thus the
macroscopic world that forms from it.
That is of course unless the computer
itself was quantum.
It was the early 1980s and a young David
Deutsch was at a party hosted by
legendary physicist John Wheeler. Ever
the gregarious host, Wheeler was
entertaining his guests with expansive
speculations about the fundamental
nature of reality and indeed had thrown
the party specifically to encourage
conversations between guests about the
topic of computing. There was an idea
circulating in physics circles at the
time, one heavily promoted by Richard
Fineman that Wheeler had become
interested in. If the fundamental nature
of reality is inherently quantum, then
how could classical computers ever
simulate reality at its deepest level?
Fineman said at the close of a 1981
lecture, "Nature isn't classical, damn
it. And if you want to make a simulation
of nature, you'd better make it quantum
mechanical."
And yet, Fineman and Wheeler, for all
their formidable intellect, knew how to
pose the question, but didn't know how
to answer it. Deutsch, however, was
different. and just a few years later he
would invent the quantum computer.
The problem facing physicists was that
as their sophistication in computing
grew, they faced insurmountable
obstacles when trying to simulate
quantum systems.
Subatomic systems were just too complex
and capturing the vagaries of quantum
mechanics pushed traditional computers
well beyond their limits. Ironically,
software could simulate the formation of
a galaxy or the dying moments of a star,
but a collection of simple subatomic
particle interactions was beyond it. And
at the root of the problem was a
fundamental incompatibility.
Classical computers, as in every single
computer used in everyday life, are
built on ones and zeros. A binary
mathematical language that reduces all
information into exceedingly long
strings of on or off states. This
mathematical language then maps onto the
states of transistors in a circuit.
They're either filled with electrons or
they aren't. But binary on oroff
languages just don't make sense in
quantum mechanics.
And so this would be a hugely important
hurdle to overcome in creating a replica
of reality for any super advanced
civilization to truly create a
functioning similacra of our universe in
all its detail or any other universe
that follows similar rules.
In the subatomic world, nothing in our
classical experience makes sense.
Particles can exist in multiple states
at once. You can't know the outcome of
an experiment until it's over.
Everything is probabilistic, and
particles don't act alone. They can
entangle with others so that the
behavior of one affects the others, no
matter how distant. All of this meant
that Deutsch would have to work out
something new. And to best understand
Deutsch's approach to quantum computers,
imagine you have a rodent problem.
To solve the problem of a mouse in your
home, you decide to buy a cat. You set
the cat loose and it wanders around from
room to room. However, you are impatient
and you decide to speed up the process.
You buy more cats, one for each room in
your house. But this solution isn't
perfect. You'll be stuck with taking
care of a lot of extra cats. And so what
if there was another quantum way to
catch the mouse? Instead of the usual
pet store, you go to Schrodinger's House
of Kittens and buy yourself a quantum
cat. You take it home, placed in a
single room, and head to bed, hoping
that this new expensive cat does the
job. And indeed, in the middle of the
night, you awaken to a noise. Getting
up, you find your quantum cat sitting
calmly by your bedside. Then you walk
into the hall and there is an exact copy
of your quantum cat and another in the
bathroom, another in the kitchen. Copy
seem to have spread throughout every
room in the house. You decide to go back
to bed. And so it is only when you wake
up in the morning that you find a single
quantum cat next to the sofa in the
living room with a dead mouse at its
feet.
The quantum cat took advantage of superp
position, the ability of quantum systems
to exist in multiple states at once.
Instead of having a lone cat prowl from
room to room, a single quantum cat
simultaneously exists in all possible
rooms. And when its job is complete, it
resolves to the solution, a single dead
mouse in a single room. To put this idea
into practice, quantum computers rely on
something called cubits. Cubits
represent the fundamental unit of
quantum computation. Unlike a
traditional computer bit, which can
either be on or off, a cubit exists in a
superp position of both on and off
states. And so by very carefully
manipulating tiny quantum systems and
keeping them stable, like the spin of an
electron or the polarization of light,
these cubits can be both on and off.
Simultaneously,
instead of a single thread of execution
winding its way through a problem, a
quantum computer can exist in all
possible solutions at once. Through
careful manipulation of the entire
quantum system, the incorrect answers
fade away, and the computer's end state
represents the correct solution.
But for Deutsch, this wasn't just a
breakthrough in computing. It was a
portal to another universe.
He remains an ardent defender of the
many worlds interpretation of quantum
mechanics which states that different
universes branch off every time a
quantum probability arises with these
different universes achieving different
results. The quantum theory of parallel
universes is not the problem. It is the
solution. He wrote it's not some
troublesome optional interpretation
emerging from arcane theoretical
considerations. It is the explanation.
the only one that is turnable of a
remarkable and counterintuitive reality.
And so for Deutsch, quantum computers
harness the power of parallel realities
to rapidly speed up computation. And
while others disagree, nobody can
definitively agree on an interpretation
of quantum mechanics, nobody doubts the
computational power of quantum systems.
Today, the most powerful quantum
computer in the world, at least that's
publicly known, is IBM's Condor machine.
It contains 1,121
cubits. Of course, that is trillions of
times smaller than the processor in your
phone. But because quantum systems are
inherently powerful, it can still solve
certain kinds of problems much more
efficiently than any other computer. And
though the computer itself is small, its
support structure is gigantic. The
processor is surrounded by an elaborate
steampunk chandelier of cooling tubes
and wires known as golden eye.
However, quantum computers aren't a
solution to all computing problems.
Indeed, they only excel in certain
special cases. And if it wasn't for the
fact that one of these special cases is
a cornerstone of the modern digital
world, the encryption that secures
internet communication, there would most
likely still today be just another
arcane study in theory.
But there is one more thing that quantum
computers can do that classical
computers cannot. They can easily
simulate the quantum world because of
course they are the quantum world.
The most important application of
quantum computing in the future is
likely to be a computer simulation of
quantum systems. Deutsch has written
because that's an application where we
know for sure that quantum systems in
general could not be efficiently
simulated on a classical computer.
Quantum computers are a macroscopic
manifestation of subatomic systems.
Classical computers struggle enormously
when dealing with quantum mechanics
because they require so much memory and
so much processing time to keep track of
all the variables associated with even a
handful of subatomic particles. But
quantum computers are designed to handle
exactly these kinds of problems. Indeed,
in a sense, the fact that they have
realworld applications is just a fun
bonus, not the reason Fineman and
Wheeler first suggested them. And so,
any kind of total universe simulator
will require a quantum component. When a
star burns hydrogen to helium, it is
quantum mechanics that dictates the
rates of reactions. When light filters
into the chloroplast of a plant cell, it
is quantum mechanics that determines how
much energy is absorbed. And even when
we speculate whether we live in a
simulation or not, it is quantum
mechanical interactions that power our
thoughts. We live in a quantum universe.
There is one further barrier to our full
universe simulations and that's the idea
of emergence.
Just because we have physical laws that
describe phenomena at certain scales
doesn't mean that we can use those laws
to tell us about other scales. For
example, we know that quantum fields
provide the backbone for force and
particle interactions. And we can use
quantum field theory to describe how
atoms work and what goes on in our
particle accelerators. But we have no
quantum field description for how a
protein folds or how neurons communicate
or how stars evolve. We have to turn to
other theories, other laws of physics
that apply in their respective domains.
Indeed, so many aspects of nature emerge
from collective action that no
fundamental theory can capture. So many
aspects of nature emerge out of the
mist. And there is one key emergent
feature of the universe that challenges
us most of all.
We are sentient beings. We are
conscious. But we are not separate from
the cosmos. We are a part of it. And so
whatever machine that can compute the
bits of the universe must also be able
to replicate our own emergent thought
patterns.
When a group of engineers at Google's
deep mind division released a paper in
2017, they had no idea that they would
be kickstarting a revolution in
computing and igniting a furious debate
about the nature of consciousness. Their
landmark paper, attention is all you
need, is now considered a watershed
moment in artificial intelligence. In
their paper, the Google engineers
devised a brutally simple scheme that
allowed a neural network, a software
replication of neurons connected
together, to capture the essential
meaning of a text by jumping from word
to word, weaving together their shared
concepts. This engine of attention gave
rise to the explosive growth of large
language models and the ability of
computers to understand the meaning of
natural language and generate long
coherent messages back to us
immediately. Some AI proponents
proclaimed that we were currently on the
cusp of artificial general intelligence
with all the broad general capabilities
that a human mind has. Though many,
however, disagreed. But what is not
under debate is that large language
models certainly don't learn in the same
way we do and don't process or store
information in the same way as a human
brain.
But if we are the end result of such an
attention engine, billions of digital
neurons firing in a vast silicon matrix,
what would that mean for us? Would that
take away our agency, our free will?
In a traditional classical deterministic
universe, we're often viewed as
biological machines. Our fates
determined by the microscopic collisions
of atoms. But of course in a simulation
the stakes are different. If our minds
are code then our thoughts are
algorithms. In such a world free will
might be nothing more than a feature of
the software. A feeling of agency
designed to make the simulation more
realistic or more productive for the
observer. And yet there is still a
glimmer of hope. Many simulations that
we run require a random number generator
to prevent the created world from
becoming a static predictable loop. In
our own universe, that randomness is
found in the quantum foam. And so, if
the architect of a universal simulation
uses true quantum randomness to drive
the simulation, then our futures might
not be pre-written. We may be living in
a program, but we would be a program
with open-ended, undetermined variables.
And so, we've reached the end of our
current computing limits. We can
simulate stars and planets and weather
and some aspects of life. And with
further advances in quantum computing,
we may be able to go deeper into the
subatomic realm than our current
technology allows.
As far as we can see, with enough energy
and ingenuity, we arguably could create
something similar to our existence, to
our universe. But of course, were we to
do so, the question would remain, what
would that mean? What would be the
consequences of a simulated reality?
Once drunk Joe dreamed he was a
butterfly. A butterfly flitting and
fluttering about, happy with himself and
doing as he pleased. He didn't know that
he was Drunk Joe. Suddenly, he woke up.
And there he was, solid and unmistakably
drunk Joe. But he didn't know if he was
drunk Joe, who had dreamt he was a
butterfly or a butterfly dreaming he was
drunk Joe.
Humans have long been questioning our
senses in the search for a base reality.
From Plato and the philosophers of
ancient Greece through India and the
search for nana all the way east to
China and the yin and yang of existence,
what we sense and what is truly real has
been a topic of fascination for
millennia.
And in 1619, Renie Deart joined that
ancient struggle by sitting alone in a
room and trying to destroy everything he
knew.
Dart has decided that if any single
belief in his head can be doubted, if
there is even a hairline crack of
uncertainty, it has to go. He wants to
find bedrock, something so solid that no
argument can ever shake it. And so he
starts taking a hammer to the
foundations of his own mind.
The senses go first. He's dreamed
vividly enough to know that what we see
and feel and hear can be fabricated. A
dream, of course, feels completely real
while you're inside it, which means the
evidence of his own eyes is worthless.
Everything he thinks he knows about the
world comes in through his senses, and
his senses can lie.
He goes further. What if there was a
demon? He supposes an immensely
powerful, immensely clever deceiver who
had constructed a perfect illusion
around him. a demon who feeds him every
sensation, every memory, every feeling
of solidity and warmth and the passage
of time. All of it false, all of it
designed to fool.
And he realizes there would be no way to
know.
The deception would be perfect. Dart
couldn't disprove the demon. He couldn't
disprove it because any evidence he
might use to disprove it would itself be
evidence the demon had provided. The
trap seemingly had no exit. All he was
left with in the cold and the dark after
everything else has been demolished is
this. He was thinking, doubting. And
doubting requires a doubter. The demon
could fake a world. It couldn't fake the
act of questioning itself.
Kato ego sum. I think, therefore I am.
And 300 years later, a philosopher named
Hillary Putnham updated Dead Card's
demon with better hardware.
Imagine, Putnham said, that your brain
has been removed from your body and a
supercomput wired into every nerve
ending feeds it a perfect continuous
stream of signals. every sensation,
every memory, every conversation, every
heartbreak, every ordinary Tuesday
morning indistinguishable from reality.
Because as far as your brain is
concerned, it is reality. How would you
know? Of course, you wouldn't. You
couldn't. Because every tool you could
use to investigate the question, your
eyes, your hands, your reasoning, your
very sense of unease regarding the idea
would itself be part of the input. The
brain in the vat has no outside view.
And neither of course do you.
And now here is where it gets even
stranger.
A cognitive scientist at UC Irvine named
Donald Hoffman ran the numbers on this
problem. However, not philosophically,
but evolutionarily.
He built computer simulations of
organisms competing for survival. Some
of his organisms perceived the world
accurately. Others perceived only what
was useful for survival. Fitness signals
are stripped of any deeper truth and the
accurate ones lost comprehensively.
The conclusion Hoffman drew is
unsettling. Evolution doesn't select for
truth. It selects for survival. Our
senses were not designed to show us
reality. They were designed to keep us
alive long enough to reproduce.
The apple looks red and round not
because it's red and round at the level
of physics. At the level of physics,
it's a cloud of mostly empty space with
vibrating quantum fields. It looks red
and round because that simplified icon
is useful, quick, actionable.
In other words, the interface you're
looking at right now, the world, is not
the computer. It's the desktop.
This is a more limited claim than Dart's
demon. Hoffman isn't saying that the
world is fake. He's saying we've never
actually seen it. What we perceive is a
species specific user interface tuned by
millions of years of natural selection
to hide the underlying machinery and
show us only what we need to function.
Reality is running in the background. We
just don't have access to it. In a
sense, he is saying that we are already
living in a simulation of our own
making. And so, if that is the case,
then it's not a huge leap to say
somebody could fool those inputs.
And in 1999, the Wowskis gave this idea
a red pill and a black leather coat and
made it into a blockbuster. The Matrix
remains the most culturally potent
version of the brain in a vat argument.
the one that made millions of people
probably for the first time genuinely
wonder if reality could be a constructed
experience.
But here's what the film gets quietly
wrong. When Neo was unplugged when he
wakes up in the grim machine world and
gasps his first breath of real air, the
film implies that he's now in base
reality.
But why would he assume that? Why would
we? If a simulation can be perfect
enough to fool you, then waking up
inside yet another simulation would feel
exactly like waking up. There's no pill
for that. The skepticism has no flaw.
And this is where Boston's argument
becomes genuinely personal. Not just we
might be simulated in some abstract
sense, but a specific almost
archaeological claim about which
simulation we probably are. Bostonramm
called it the ancestor simulation. His
reasoning was this. An advanced
civilizations wouldn't just simulate
random universes. They would simulate
their own past, their own history, the
evolutionary pressures that produced
them, the civilizations that preceded
them, the individuals whose choices
shaped their world. For these advanced
civilizations, these would be the most
scientifically and philosophically
interesting simulations to run. the ones
that explained how they got here.
And Boston speculates they would run
them again and again and again. And this
would mean that if simulated beings are
possible at all, most of the conscious
beings who have ever lived would be
those simulated ancestors.
Reconstructions run millions of times in
millions of parallel branches by
civilizations curious about their own
origins. We would not just be living in
a simulation. We would be the
experiment, the historical reenactment,
the digital zoo.
And if that wasn't enough, there is an
even more extreme version of this idea.
Suppose we build a computer so powerful
that it can simulate a universe as
complex as our own. Within that
simulation, those digital beings would
also eventually become curious. They
might build a simulation of their own.
This is the grim concept of nested
simulations. If it is possible to create
one, then there were likely countless
numbers of them stacked like Russian
dolls. The natural universe, the one
made of real meat and bone, would be
buried under trillions of layers of
digital replicas, each making their own
digital replicas. Statistically, the
odds that we are in the base reality or
anywhere near it become vanishingly
small. We would likely be just a sub
routine within a sub routine. A dream
within a dream being processed by a
machine that we would never see.
And so clearly, were we to inhabit a
sufficiently complex simulation, it
could fool our brains. We would have no
way of telling the difference between an
artificial world and the real one. No
way of experiencing reality beyond our
own tricked senses.
But if that is what we are, if a first
kiss quickens our pulse, if grief lands
in our gut, if the sunset still takes
our breath away, then in what sense is
it any less? In a way, a perfect
simulation is not a copy of the
universe.
It is a universe.
What is reality at its most fundamental
level if not information?
This brings us to the ultimate challenge
of physics. The question of what
everything really is. And one man was on
a mission to figure it out.
The year was 1944.
A worn postcard weighed heavily in John
Wheeler's hands. It had been sent from
Europe from his brother Joe on the front
lines as Allied forces made their final
push into Nazi Germany. The war was
close to one, but Germany was still a
potent and dangerous threat. Joe knew
that his brother was working on
something big. It was a secret project
far beyond the pay grade of a lowly
grunt. But Joe suspected, as did many
other soldiers, that some of the
smartest scientists in the world were
gathered at laboratories and facilities
scattered throughout America. All
focused on a singular effort to produce
a weapon so powerful that could end the
war entirely. And yet, every day, more
lives were lost in the pursuit of
ultimate victory. They were eager for
any reprieve from the violence. And so
Joe wrote only two words on that
postcard.
Hurry up.
And just a few months after Joe sent
that postcard, he would be dead. John
Wheeler was too late to save his
brother.
Here we are so close to creating a
nuclear weapon to end the war. We would
later write, "I couldn't stop thinking
then and haven't stopped thinking since
that the war could have been over in
October 1944."
From that day, Wheeler would commit his
entire intellect to solving the
fundamental nature of reality. The past,
Joe's death, was forever locked away
from him, inaccessible. Why did the
cosmos behave the way it did? What rules
governed the universe? and how could we
discover them? Indeed, Weither is
perhaps the most influential physicist
that is not really a household name. He
was a postoc under Neil's bore and went
on to mentor over 60 graduate students
and over a 100 undergraduates and
postocs. Wether's core philosophy was
grounded in radical conservatism. He
based his research on known physical
laws but pushed them to their utmost
extreme. And so in 1976, Weither
assembled a team of students and postocs
at the University of Texas to study the
nature of quantum information. One of
these postocs was David Deutsch, who'd
go on to kickstart quantum computing.
But Wheeler was really interested in
something even deeper.
Where does reality come from?
To explore this question, Wheeler took
the familiar two slit experiment and
showed just how absurd reality can be.
If you send a line of photons through
two parallel slits, you can't know which
one it passed through. What you observe
is even after the photons have crossed
over an interference pattern on an
opposite screen, exactly as if waves of
water had passed through the device. But
if you cover one of the slits, the wave
pattern goes away and the photons act
like a particle. A bizarre outcome of
quantum principles, showcasing the wave
particle duality of nature. However,
Weether went one step further and
created a truly bizarre thought
experiment.
What if you timed it so that you started
with two slits, then after you knew the
photon had passed through, you closed
one of them off? Would the photon know
that you had closed one slit behind it?
And if so, what would emerge on the
observation screen? His conclusion,
borne out later by experiment, is hard
to swallow. If you close one of the
slits behind the photon, it acts as if
the slit had been closed the whole time,
and the photon collapses into a particle
instead of interfering like a wave. Just
how is this supposed to work? How could
a photon reach back in time to see what
you chose to do well after it had passed
through the experiments? Why did the act
of observation affect both the future
and the past?
Wheeler's solution was information.
It from bit was the phrase he coined for
this philosophy/physics.
He viewed the universe as a sort of
self-exited circuit where the act of
measurement gave rise to physical
reality. In this view, the cosmos would
be a buzz with quantum information
sloshing back and forth in entangled
superposed states. And it would be the
act of observation that would turn these
probabilities into concrete existence.
For Wheeler, that was it. That was
reality. A series of observations.
Indeed, without observation, there is no
measurement. The time and place don't
matter. What is essential is
information, and when it is measured.
When Paul Dak challenged this idea
during a lecture, he asked Wheeler if we
create the moon every time we look at
it. Yes, was Whether's blunt reply.
We would never be able to build a
coherent theory of physics from this
radical idea. But the kernel of truth
that remained was that information was
key to physics. Energy, momentum,
quantum states, and everything else
within physics can all be cast in terms
of information. Information shuttling
back and forth under certain rules. For
Wheeler, that was the end of the line.
Information was the central pillar of
existence. But is there any evidence
that supports this world view? To the
skeptics of the late 20th century,
Wheeler's it from bit sounded less like
physics and more like poetry. After all,
a bit is an abstraction, a choice
between yes and no, one and zero. How
could something so ethereal, so devoid
of substance, give rise to the cold,
hard weight of a mountain, or the
searing plasma of a star?
Well, one answer lay in a discovery made
in 1961 by a German American physicist
named Rolf Landau.
Landau worked for IBM, a company that at
the time was obsessed with the
efficiency of its roomsized mainframes.
Indeed, Landau wasn't looking for the
secrets of the cosmos. He was looking
for the limits of the machine. He wanted
to answer a simple question. Is there a
minimum amount of energy required to
process a single piece of information?
Through his work, Landau realized that
when you erase a bit of information,
whenever you take a one or a zero and
reset it to nothing, you must, by the
laws of thermodynamics, release a tiny
puff of heat into the environment. It's
fairly straightforward. You are reducing
one or zero two states down to a single
state. Nothing. Entropy is therefore
reduced. And since the second law of
thermodynamics states that local entropy
can never decrease, entropy somewhere
else must go up to balance out the total
entropy, then that entropy takes the
form of heat. And this isn't merely a
flaw in our wiring or the result of
inefficient copper. It is a fundamental
tax levied by the universe itself.
If you want to delete the thought from a
digital brain, the universe demands a
payment in energy.
This became known as the land hour
principle and was the first concrete
evidence that information is not just
about the physical world. It is a
physical thing in its own right.
Changing information has a price. It has
a temperature.
And so logically it follows that if
information has a physical cost then
every interaction in the universe, every
photon striking an eye, every electron
hopping in a circuit, every chemical
bond forming in a cell is a form of
computation.
And in 2002, Noble laurate Anton
Zylinger took the idea one step further.
In the quiet laboratories of Vienna, he
took Wheeler's radical dream of an
information processing universe and
translated it into a hard experimental
reality. By peering into the heart of
the most elementary quantum systems such
as the spin of a single electron,
Zylinger demonstrated that these
particles are the containers for exactly
one bit of information.
This means for over a century we have
grappled with why our universe is
quantized existing in discrete
irreducible chunks of energy and matter.
Zylinger's work suggests that physics is
quantized because information itself is
quantized. Nature doesn't come in
packets because of an arbitrary physical
rule. It comes in packets because a
single bit is the smallest possible unit
of truth the universe can hold.
And so perhaps we's crazy idea doesn't
seem so crazy after all. If the universe
is constantly processing information and
that information has a physical
footprint, then perhaps the cosmos isn't
just a collection of objects that happen
to have data. Perhaps the cosmos is the
data itself manifesting as objects.
Perhaps at the very limit of reality,
the it doesn't just emerge from the bit.
Maybe the bit is the only thing that was
ever truly there.
The key argument in favor of simulation
theory is that if the universe is made
of bits, then the universe is by
definition computable. And if it is
computable, then someone somewhere might
have already built a machine powerful
enough to run the program. Indeed, in a
sense, we've already done it, at least
partially. And so, if computers are
capable of recreating the universe, then
what's stopping the universe from being
a simulation? John Wheeler spent his
whole life arguing that information is
not a representation of reality. It is
reality. The bit is the thing. It's all
one and the same in the it frombit
worldview.
Indeed, it's clear that at the moment we
can't rule out the possibility and so we
have to return to the grim apocalyptic
reasoning of Nick Bostonramm.
However, there are other ways to get
around Boston's argument. One is the
argument that we know for sure we
haven't created simulated consciousness
in our own past. Nor have we met any
aliens who have demonstrated the
capability or indeed any aliens at all.
Boston's entire argument rests on the
ability to do it in the first place. And
until we someday do it in the future or
we meet aliens who already have, then we
can never truly know for sure if it is
possible. Indeed, some scientists like
David Kipping have attempted to
calculate the probability that we live
in a simulation based on the extremely
limited data that we have access to.
Namely, that we ourselves can't create
simulated conscious beings and we
haven't met anyone else who can.
Unfortunately, his calculations arrived
at almost exactly 50/50 odds, which
isn't hugely helpful.
And so all that remains from
Bostonramm's argument, all that's left
after our magnificent advances in
simulating the universe and what meager
scraps of truth are laid bare after
decades of wheelers searching is a
rather unsatisfying answer. We might
live in a simulation and we might not.
And we're a long way off from knowing.
Either way,