Have you ever seen The Matrix? Chances are that you have, it's a rather popular film.
In one particular sequence the protagonist Neo is presented with a conundrum.
The red pill or the blue pill. A choice between learning the absolute truth behind reality and the
blissful ignorance of illusion. Neo eventually decides to take the red pill and does indeed
learn the truth, as horrifying as it may be. He learns that he's been living inside a simulation
this whole time and he is now finally experiencing true reality. At least that is what you, the
viewer, is led to believe. But an aspect that is somewhat dismissed is that the red pill
doesn't grant you knowledge of reality as much as it completely eradicates any distinction
between real and fake. Let me ask you this. When watching the movie, did you ever question
if the supposed true reality that Morpheus and the gang exist within is actually true reality?
What's to say that they are not inside a simulation themselves? I mean, up until
this point, The Matrix was just as real as this newfound reality. If anything, The Matrix
only proves that knowing what reality is and is not is an impossibility. And this could
potentially go on for infinity. Never reaching any sort of true actual reality if that even exists.
Just a simulation within a simulation within a simulation within a simulation...
Yeah, and so on, and so on, and so on, and so on...
This video is not really about The Matrix per se, but it's hopefully a digestible introduction
to the profound and intricate topic of this video.
The idea that the universe and reality itself could be a simulation is not something new.
We can trace similar ideas as far back as the time of ancient Greece when numerous philosophers,
around the world, alluded to the idea that reality could be an illusion. Chinese philosopher
Zhuang Zhou compared his own existence to that of a dream in which he believed himself
to be a butterfly. He questioned the distinction between reality and a dream if both could
seem equally real. Another example is Plato's Allegory of the Cave. The first part goes like this.
Imagine a cave where people have been imprisoned since birth. They are chained in such a way
that they are forced to constantly gaze upon the wall in front of them. They cannot look
around the cave, at each other, nor at themselves. All they know is this wall and nothing else.
Behind them there's a fire, and between the prisoners and the fire, there's a walkway.
When people walk between the fire and the prisoners, shadows are cast upon the wall.
Because the prisoners doesn't know anything else, they believe the shadows to be real.
Actual entities of their own. And when a passerby is talking, the prisoners believe it to be
coming from the shadows themselves. They have no idea that the shadows on the wall are merely
lesser copies of reality and falsely assume that this
partial reality that they can perceive is the complete truth.
There are many interpretations of this allegory which can by applied to vast range of topics.
It can be interpreted as a way of understanding the importance of knowledge and how it shapes
reality or it could be an analogy for human ignorance and our
unwillingness to seek truth and wisdom. It could also be read like this.
Just like the shadows in this cave, could our perceived reality be a shadow of something else?
In physics and cosmology there's now a subfield called digital physics which is a collection
of theoretical perspectives based on the premise that the universe is describable by information
and as such is computable. And some of these physicists around the world are actually trying
to find out if our universe could be a simulation. Commonly referred to as the Simulation Hypothesis.
This is done by, in various ways, comparing the real world against our own technology.
If certain similarities are found, conclusions can be drawn. One such study titled
Constraints on the Universe as a Numerical Simulation concludes that it is possible.
A really simple analogy is to think of the pixels on your screen that make up this video right now.
When I move this red dot across the screen, we perceive it as a smooth sliding action.
But we know for a fact that this is an illusion caused by the limitations of our sight. Nothing
is really moving it's just bits of information being modified in such a way that, from our
perspective, it's perceived as motion. If we zoom in and slow down, we notice that the
red dot isn't sliding as much as it snaps to each individual pixel. And this is essentially
what they have observed, that the universe has a finite resolution, or an underlying
lattice as they call it. This could mean that the universe and reality is not made out of
energy or matter but is instead made out of quantized bits of
information that, from our perspective, is perceived as energy and matter.
Another way to imagine a computational universe is using what's known as a cellular automaton.
A cellular automaton consists of a grid of cells. In this case, each cell can either
be populated or unpopulated. We then need to specify a set of instructions so that the
state of each cell evolves over time based on the state of neighboring cells. It may
sound complicated but it really isn't. Let's start with something simple. For example,
we could say that each unpopulated cell will become populated if a populated neighbor is
found to the left. We then populate a single cell and execute the program. What happens
is that for each increment of time a new cell is populated to the right of every populated
cell. So in this case, it just continues to the right forever. Not very interesting. Let's
make it a bit more complicated by using the instructions
of a popular cellular automata known as The Game of Life. These are the rules:
#1. Each populated cell with either one or no neighbors becomes unpopulated.
#2. Each populated cell with four or more neighbors also becomes unpopulated.
#3. Each populated cell with two or three neighbors remains populated.
#4. Each unpopulated cell with three populated neighbors becomes populated.
We populate as many cells as we'd like and then press play. The resulting behavior is
actually quite remarkable. I mean it's not GTA V or anything but still. What's remarkable
is that these four simple instructions can over time produce incredible complexity. Cells
can live, die, or multiply and create a sea of seemingly chaotic randomness. Some configurations
stop immediately while others seem to continue forever. And there is no guaranteed way of
telling if any specific configuration is eventually going to stop or continue indefinitely. If
we zoom out as the model continues to expand, increasingly complex patterns begins to emerge.
But not only patterns. Over time even the behavior changes. The interactions between
individual cells is overshadowed by the behavior between entire blocks of cells. And this is
the idea. That the universe began as something incredibly simplistic like a grid of cells governed
by a few simple instructions. But given enough time it evolved into something incredibly complex.
It's only natural for us to assume that the complexity of the universe must be very complicated.
The world can often seem very confusing, random, unpredictable, and even unexplainable. What
The Game of Life quite elegantly illustrates is that complexity can actually be the result of simplicity.
If you, and I, and everything around us is the result of computable information, it stands
to reason that that information can be modified and manipulated to an endless extent.
We would be nothing more than puppets in a theater.
Maybe the simulation began seconds ago and we only think it's been 13.9 billion years
because that information was artificially included upon its creation. Maybe the universe
is really really tiny and all distant celestial bodies are simplistic renditions to create
the illusion of enormity. Maybe nothing physically exists until we observe its existence. Perhaps
detail and complexity is added when it's needed instead of being constant and absolute. Perhaps
discovering that this is all a simulation is part of the simulation. Perhaps this isn't
the first iteration of the universe and someone could be pressing the off switch right n-
Don't get me wrong. All of what I just said is absolutely insane.
But that's kind of my point.
If we accept the simulation hypothesis, we also accept that literally anything is
possible and that nothing can be determined. Imagine that we somehow found definitive proof.
So for the sake of argument, let's say we escaped the simulation. Then I think we could all agree that we
would know that it's a simulation, right? But we still wouldn't know if our escape from the
simulation was simulated in and of itself. In other words, we could still be inside the
simulation. It's a so called infinite regress issue which means that any evidence we find
or knowledge that we obtain could just as well be simulated in and of itself.
Including any evidence that it's not a simulation.
As the extent of the illusion cannot be determined, nothing can be determined.
In the first draft of this script I addressed many radical ideas surrounding the
simulation hypothesis. But as it can all be nullified by the asking: "What if it's part of the simulation?".
It's really not that interesting. There's little, if any, scientific value here. It's mostly
philosophical and metaphysical. And it's all very analogous
to the limited reality of the prisoners in the cave.
So let's change our perspective. Instead of assuming the position of the prisoners in
the cave, could we be the ones who ignite the fire to cast shadows upon the wall?
A big reason why ideas related to simulating reality has become so popular in mainstream
media, like movies and video games, is that on the surface it seems very plausible.
If we look at what we could do just a few decades ago and compare it to modern technology, it's
easy to imagine a future wherein technology has advanced far enough that it's indistinguishable
from reality itself. And while there's nothing that explicitly prevents that from happening
in the future, there are definitely limitations to what we can and cannot do.
Over the past half-century the processing power of computers has doubled every two years
which is an observation known as Moore's Law. But this growth won't continue forever. In
fact it's already begun to slow down. It's now closer to two and a half or even three
years. The reason for this decline is due to the physical limits of computation. Computers
are fantastical and can do incredible things but they are not magical. The speed at which
they process information and the amount of information they can process is, like everything
else, governed by the laws of physics. For example we will never, regardless of any potential
futuristic technology, be able to accurately replicate anything down
to every single molecule, atom, and fundamental particle.
And the strange world of quantum mechanics is to blame. There are many reasons why
quantum mechanics makes this impossible but one great example is the uncertainty principle.
It states that the more precisely the position of a particle is determined, the less precisely
the momentum of that particle can be determined and vice versa. You can think of this as a
balancing board. We force the left side down to increase precision in measuring the position
of a particle, but in doing so, the right side has to go up and thus we loose precision
in measuring the momentum of the particle. To be certain about both properties at the
same time would require us to break the board, or in this case, break the laws of physics.
The uncertain and probabilistic nature of the universe makes exact replication an impossibility.
So let's forget about any notion of exact replication. It just isn't, dare I say, realistic.
What we can do instead is mimic reality by approximation. Take a look at this.
This is The Illustris Project. A giant cosmological simulation with the aim of studying the formation
and evolution of galaxies. It's an ongoing project in which scientists use the most precise
data and calculations currently available to create the most precise model of the universe
possible. At its highest resolution it had a volume of 106.5 Mpc³, took several months to complete on
a supercomputer with 8192 cores, used 25 TB of RAM at its peak, and had a particle count of over 18 billion.
Of course, it's only realistic to a certain extent and from a very narrow perspective.
The simulation is detailed enough that they can actually
zoom in on individual galaxies, but it's not detailed enough to simulate the birth of each
individual star or planet. And certainly not the astronomical numbers of individual molecules,
and atoms, and so on. Instead they have to approximate how a galaxy behaves as a whole without actually
simulating all of it's individual parts and properties. And once the simulation arrived
at present day, the result was strikingly similar to what we observe in the universe.
And by constantly tweaking these approximations increasingly
realistic results can be achieved. Never quite reaching true realism but hopefully realistic enough.
This is all well and good for all scientific endeavors. Things like astrophysics, particle physics,
meteorology, fluid mechanics, medicine, evolutionary biology, and the list goes on and on.
But what about creating a simulation for entertainment purposes?
So far I've only talked about simulations as self contained systems. You write some
code, press execute, and hope for the best. But wouldn't it be far more interesting to
create simulations that we can not only interact with but also experience to the point of complete
immersion. Software like video games are great examples of interactive simulations and hardware
like the Oculus Rift and the HTC Vive are some of the most immersive technologies available
to the public. Well they will be soon at least. Of course, these are only aimed at stimulating
the audio-visual senses. What about everything else? Like touch for example. Well, there's
full body suits like the Teslasuit, vests like the KOR-FX, and gloves like the Hands Omni.
These will give the illusion of actually holding virtual objects, getting hit by bullets,
and possibly even give the sensation of temperature. Then there's also entire systems built to
create a virtual experience, usually designed according to a specific game or game type.
There's driving and racing simulators, flight simulators, railway simulators, etc. If you want to navigate
inside a virtual environment, your best option at the moment is something like the Virtuix Omni.
All of these technologies are fantastic but they are not ideal. They are only the beginning
of the virtual reality revolution that likely waits ahead. They are the monochromatic TV's
before color. Because the limitations of these devices stems from their implementation. You're
always going to be aware that you're wearing a head mounted display or that you're strapped
into a locomotion platform. What's eventually going to replace these mediating technologies
to create a truly immersive experience are BCIs. Brain-computer interfaces.
Research on BCIs began in the 1970s and since then the technology has come a long way. So
far the focus has mostly been on repairing cognitive and sensory-motor functions. As
an example neuroprosthetics are prosthetic limbs that can be controlled by a persons
brain. People who's lost an arm and hand can now get a robotic prostheses that they can
control using sensors implanted in their brain. BCIs can also be used to allow paraplegics
to walk again and help people with many types of paralysis. From an entertainment perspective,
you can truly see its potential when combined with virtual reality. The Emotiv EPOC is a
publicly available BCI that you can actually use to play games with your mind. I mean,
it's not perfect, it's actually far from perfect but come on. You just cannot complain when
someone has quite literally invented mind control. And better yet in 2014, the first
brain-to-brain communication was achieved between two people via the internet.
In other words, telepathy is now becoming a reality.
But we're still missing a crucial aspect. That is CBI technology. A computer-brain interface.
And this is a significantly more difficult obstacle to overcome. In a typical brain-to-computer
interface, a device receives information from the brain and tries to interpret what that
information means. The worst that could happen is that the computer gets it wrong. In a computer-to-brain
interface, the brain receives information from a device and the worst that could happen
is that you actually damage the brain of the user. In 2002, a blind man had a device implanted
onto the visual cortex of his brain which was in turn connected to a camera. This allowed
him to partially regain his vision. The camera sent its signals to the visual cortex of his
brain and his brain interpreted these signals as if they actually came from his eyes. Another
example of a CBI was used on monkeys. A monkey would control a virtual arm to touch one of
several visually identical objects. When the virtual arm touched one of the objects a signal
would be sent back to the brain of the monkey to stimulate the sensation of touch,
describing the fine texture an object that didn't actually exist.
But there's definitely a greater risk at play here and it's gonna take a while until we
perfect such technology. But once we've unlocked the
mysteries of the brain, the possibilities will be virtually endless.
If this technology continues to advance and is able to entirely escape the realm of science
fiction, the world as we know it and the future we often imagine, will dramatically change.
When we try to imagine the distant future, we often think of humanity as these grand
explorers of the universe. It's often just assumed that we will continue to expand outwards
far beyond the Earth and the Solar System. Of course, this is under the optimistic assumption
that no apocalyptic events takes place and that we steadily continue to progress and
innovate. Almost every non-apocalyptic futuristic science fiction tale describes humanity as
a species that will expand outwards. And maybe that's true. But when this technology turns
into reality, why would you want to? A powerful virtual reality could allow us to do anything
and everything. No fear of harm or death, no irreversible consequences for your actions,
no physical limitations. The ability to customize and manipulate the world around us to fit
our personal needs and preferences. Just like in a dream, maybe it's possible to manipulate
the brain's sense of time. Real world minutes could turn into virtual years. Could that
be why the universe can seem so lifeless even though it's been around for such a long time?
Perhaps every civilization that reaches a certain technological maturity realizes that
expanding outwards to explore the universe is pointless when
expanding inwards, using technology, allows you to do so much more.
I've never made a video like this before. A video heavy on speculation and even touching
on some philosophical questions. Hopefully you don't think I've gone completely insane.
It's so difficult to make a video about these topics without sounding like you have some
sort of religious faith in The Matrix, waiting for Morpheus to come down from the heavens.
It's far fetched, highly speculative, and mostly just fun to think about.