I’ve been kicking this one around for a few years now and some of you will even have heard me talk about it already. Every year that passes it seems a little more appropriate.
Simulation is a powerful tool that we use to discover things about our own world that we can’t directly observe. Computer simulations are becoming ever more intricate and accurate and they will continue to advance. We already create simulated worlds, simulated creatures, simulated humans. One day soon, someone clever will realise that *evolution* is now a tool that we can use in a simulated environment. We can plug in the parameters of a world containing (simulated) life, fast-forward the simulation a few million years and see which fascinating creature evolution delivered to the top. Someone clever will also soon realise that we can extend that idea to manufacturing design. We can pit potential designs against each other in a made-up world in which the parameters have been tuned to ensure survival of the fittest design with random mutation across generations providing the variation. Once that happens, all kinds of weird and wonderful ideas will pop out of an algorithm that no human could ever have thought of. It’s coming. It’s inevitable.
When we have this capability, of *course* somebody’s going to apply it to our universe – I can imagine plugging in the deduced construction of the universe a trillionth of a second after The Big Bang and then rolling forwards to see what happens. The first time we do it, it will end up nothing like our current universe looks. So we’ll tweak the parameters, maybe tinker with the cosmological constants, play with some new rules. We can even use the evolution idea here, and get our computer to run billions of simulations and pitch them against each other. With such huge numbers of simulated universes going on, somewhere there’s going to be a cluster of stuff that evolves into humans, just like us. For the simulation to work, clearly those beings can have no evidence that they are indeed simulated (otherwise it isn’t a representative simulation) – they will feel like they live and breathe and see and love, with no idea that it’s all zeroes and ones (or qubits!) inside a machine from an advanced civilisation. After a while, those beings will start making simulations of their own and we go a bit fractal.
The video game “No Man’s Sky” (https://en.wikipedia.org/wiki/No_Man’s_Sky) is due for release in 2016 – it features literally quadrillions of planets, because they’re generated by an algorithm rather than being mapped, and those planets have variations of life on it. There are so many planets that most of them will never be seen by any human, ever. This is a *video game*. We’re nearly at the critical mass already.
Of course, you can see where I’m going with this. For a simulation of our universe to work, the humans have to believe they’re “real” (whatever that means) and so they are 100% indistinguishable from *us* here today. A real human has exactly the same inputs and outputs as a simulated one, so if you *are* one, you can’t tell whether you’re real or simulated. And the thing is … there’s only one real universe. Only one “top of the tree”. As soon as simulations start making simulations, you’re into an infinite spiral downwards, which means that for one of us real-or-simulated humans, it’s infinitely more likely that we’re in one of the twig universes rather than the one single universe at the top.
That’s a pretty mental thought. The only axiom I’ve used is that we will continue to make ever-more complicated simulations and that seems to lead logically to a mathematical *certainty* that we live in a simulated universe.
Not only that, but this simulation (or its root ancestor simulation) was programmed by somebody – *created* by somebody. So our universe has a creator?!
Oh shit. Have I just proved the existence of God?
I need a lie down.