Every single thing made up of matter in the universe is a combination of about a hundred or so atoms, plus a few variations of each (isotopes). Every mineral, every compound, every substance, every protein, amino acid, even DNA itself is a sentence made up from a dictionary containing about a hundred words; the elements in the periodic table. And each word in that list is composed of different combinations of three letters: the proton, neutron and electron. To put it another way, as an organic chemist friend of mine described it, all you need to do any kind of chemistry you want is just three subatomic particles.

Of course, nothing is quite that simple. There are the anti-particles, and there are all those exotics that are produced in radioactive decay and in atom smashers, and there are the components of other particles (quarks)
plus things like photons and neutrinos. But still, we’re talking about at most several dozen particles so far identified by physicists, and many of them may be just non-essential flukes that are produced in violent events and exist only for a short time.

That’s a pretty small alphabet, and with just a few rules spelling out how and which are allowed to combine into words, you can make anything you want, with plenty left over to store the spelling and grammar rules.

Alphabets are just information, so the universe could certainly be considered as a dictionary, just data, and a few rules for how to manipulate it (the laws of physics). The entire universe could be simulated by data bytes of only a few bits each, Just like any computer program written in source code is just a bunch of keystrokes in a certain order. So you don’t need “hydrogen”. All you need is proton and electron letters and some rules for how they interact with all other particles. There is no reason in principle our universe couldn’t be a simulation running on a computer somewhere, or a thought in some mind somewhere. In fact, that computer or that mind could exist in a real universe very different from ours, or even in a universe very similar to ours, one where matter and energy, space and time exist just like they do here.

You could argue that we are self-conscious beings, not simulations (the old “we are souls, not machines” argument). But if our own ordinary universe was able to evolve consciousness, why couldn’t an artificial (or should I say “artifactual?”) one be able to do the same thing? It could be programmed to be able to do so.

So why do we create simulations? That might give us a clue as to how the programmers of our universe think and work. We create simulations for sport (games) for study of phenomena too cumbersome to reproduce in the laboratory (like weather models), for training purposes, or for predictive exercises (Let’s see how a general nuclear war would work out if WE struck first?).

Its hard to speculate on how those who are writing our simulation think. But there does seem to be one thing about them that is pretty safe to predict. They can probably turn the whole thing off whenever they’ve learned what they need to know. Remember, they aren’t necessarily running a simulation of our civilization to learn how its going to turn out. We may be just an irrelevant by-product. Perhaps the Great Programmers are running simulations on how galaxies evolve, or on different proposed values of pi, or variations on the speed of light, or Planck’s Constant, and our civilization and history is just a minor by-product that has nothing to do with what they’re really interested in.

And even if they knew we were here, they could still just as easily write us out of the program, just as a novelist could eliminate a minor character because he does nothing to advance the plot.