The Is: The SImulated Universe

OK, back to the war and that means back to the blog. 

In our last  few chats we've been discussing the idea of parallel universes.  First of all we considered if the universe we inhabit is infinite.  If it is, then the particular collection of atoms in our solar system must be exactly recreated elsewhere, if you just travel far enough.  On average, if you walk about a googolplex steps, you'll find another identical solar system with another you sitting there reading this blog (except for the fact that, being identical to you, he also took off to see what his doppleganger was up to in another part of the infinite universe).

We talked about string theory briefly, and how our mathematical laws and constants are, according to string theory, based on the topology multi-dimensional strings and branes, and that those topologies allow for, at present, the possibility of around 10⁵⁰⁰ (that's a one with 500 zeroes after it) different kinds of universes with physical laws that may differ radically from what we know.

We talked about the quantum multiverse.   Evidence shows that subatomic particles tend to exist as probability waves and when they are observed, all the other probabilities collapse except for the thing that actually happens. But what if each of those probabilities doesn’t collapse?  What if, upon observation, each possibility realizes itself in a parallel universe, and thus billions of new universes are being created each nanosecond for every single possible outcome of a quantum event.

The last type of parallel universe we will discuss is the simulated universe.   If you are in tune to pop culture at all, you already know what this is:

Sorry, which pill was which again?

One of the largest supercomputers in the world, Blue Gene, is presently doing a passable job of effectively simulating a tiny portion of a rat's brain, about the size of a pinhead.  It's modeling about 10,000 neurons comprising some 10 million neural connections.  Big deal,  say you?

Why sure, it's a far cry form the 100 billion or so neurons we have in our head, comprising trillions of neural connections and operating at about 100 trillion operations per second.  But when you take into account the astounding progress in computing ability, the project's leader, neuroscientist Henry Markram, figures that we'll be effectively modeling a human brain by about 2023.

Let's keep moving.  Let's say that we get a handle on quantum computing in the next few decades or so.  An effective quantum-based computer the size of a laptop could not only model a human brain, it could model every thought of every human ever in a fraction of a second.  So computing power isn't really an issue, barring a zombie apocalypse.

 If you've got a machine that can effectively model a human brain, shouldn't you be able to simulate people?  Well, now we're out of the cut-and-dried world of circuits and into the more ethereal realm of epistemology.  Would your simulation think and feel the same way you do,?  Would it be self-aware?  Or is their some ineffable quality to consciousness that lies beyond the ken of mere computation?

This an active and interesting area of research in epistemology, and one perhaps we'll discuss in a later Mindfingers post.  But let's say for the time being that, for the purposes of any human interrogation, we cannot differentiate between you and your simulation.  That is, if we put each of you in a locked room and asked questions by slipping pieces of paper under the door, there is nothing we could ask that would allow us to tell you apart from your simulation (known as the Turing Test for artificial intelligence).

So now we have human mind simulations that you can't tell from the real thing.  After that it would be child's play to simulate a physical universe for these minds to live in, with stars in the heavens and gravity and clouds and viruses.  In essence, you've created a parallel universe.  Unless you decide to tell the simulated beings in your model that you are there, they would more or less be in the same situation we're in--looking around and wondering what they are doing there.  This seems much easier than creating an actual parallel universe, and the forces involved with that.

If we could create one of these simulated universes, there is nothing to stop us from creating several.  We could play with them and try out different things.  Perhaps, in the future, we could even find a way to live in them ourselves.  And we might have at some point millions of these simulated universes.  A few on every laptop.

So here's the thing.  In the vastness of The Is (my name, recall, for the multiverse), do we honestly think that we are the first life form ever to become this technologically advanced?  Indeed, it would seem likely to the point of almost certainty that civilizations elsewhere had or have reached our level of technology and beyond.  And if that's the case, they've already discovered this idea of simulated universes too.  Perhaps millions of intelligences elsewhere in The Is have already created simulated universes..

Not only that, but these simulated universes, being more or less perfect-fidelity copies of the real ones, could have simulated inhabitants that themselves create simulated universes with simulated inhabitants, who may in turn create their simulated universes.  In this scenario you end up with simulated universes vastly outnumbering "real" ones.

Following that thread of logic, if simulated universes are far more probable than real ones, then it follows that it is far more probable that we ourselves are living in a simulated universe than a "real" one.

In the immortal word of Keanu Reeves: Whoa!

So with our potentially infinite universe, parallel universes from other Big Bangs, alternate universes possible in string theory, the Many Worlds Interpretation of Quantum Mechanics and simulated universes, we have a vast multiverse beyond our furthest imagining.  Infinities upon infinities of universes.

There is only one step left.  What if the multiverse simply comprises everything.   There is nothing that isn't. No matter how far-fetched your imagining, it is out there right now.  Harry Potter living on Privet Drive.  A universe composed of nothing; not empty, but nothing.  A universe where pi = 4.  A universe like ours, but running backwards.  An entire multiverse ruled by a omniscient, omnipotent God. 

The Is.

If you're interested in this kind of stuff, I highly recommend Brian Greene's book The Hidden Reality.