Stoner #1: What if, like, I’m not really here? I mean, what if you’re just, like, dreaming me?
Stoner #2: Yeah. Or what if, uh, neither of us is here, dude? I’m mean, what if we’re, like, just part of a computer simulation? Like in that Keanu Reeves movie?
Stoner #1: Bill and Ted’s Excellent Adventure?
Stoner #2: No, dude, The Matrix.
Stoner #1: Jim Morrison was in The Matrix?
Stoner #2: No, dude, Keanu Reeves was.
Stoner #1: Yeah. Right. Pass the bong.
Stoner #2: You’ve already got it, dude.
Stoner #1: Uh, yeah. Right.
While it may be a popular topic among stoners, the question of whether we may be living in a simulated reality has also been subject to academic debate. For example, in 2003, Nick Bostrom – Professor in the Faculty of Philosophy at Oxford University – published a paper entitled Are you living in a computer simulation? The mind-bending starting point for Bostrom’s work goes like this:
This paper argues that at least one of the following propositions is true: (1) the human species is very likely to go extinct before reaching a “posthuman” stage; (2) any posthuman civilization is extremely unlikely to run a significant number of simulations of their evolutionary history (or variations thereof); (3) we are almost certainly living in a computer simulation. It follows that the belief that there is a significant chance that we will one day become posthumans who run ancestor-simulations is false, unless we are currently living in a simulation.
Hmmm. Okay. Let that run a few laps around your synapses.
Since it’s one thing to postulate that we might be nothing more than lines of code running inside the mother of all computers, it’s quite another thing to actually prove or disprove it.
Yet that’s precisely what a team from the University of Bonn led by nuclear physicist Silas Beane is planning to do.
They contend that if we are living in a computer simulation, then that simulation must invariably have some observable limit or cut-off point – and that they can establish whether those limits do indeed exist by creating their own simulation of the universe.
Now, the science is extremely complicated and I certainly don’t claim to understand it, but the basics would seem to be that a computer simulation – be it the simulation in which we may be living or the one to be created by Silas and his team – must be built around a three dimensional lattice that advances in steps of time. Cosmic rays would, seemingly, travel preferentially along the axes of the lattice and so be more concentrated in certain locations. Consequently, if the cosmic rays in the University’s simulated universe – which will be identical to the real universe in every way except size – are concentrated along axes, then that would be a clear indication that those axes are also present in our universe. In other words, it would prove that we’re living in a computer simulation.
One of modern physics’ most cherished ideas is quantum chromodynamics, the theory that describes the strong nuclear force, how it binds quarks and gluons into protons and neutrons, how these form nuclei that themselves interact. This is the universe at its most fundamental.
So an interesting pursuit is to simulate quantum chromodynamics on a computer to see what kind of complexity arises. The promise is that simulating physics on such a fundamental level is more or less equivalent to simulating the universe itself.
There are one or two challenges of course. The physicsi