I've been invited to be one of four humanities panelists after a public lecture on the early history of the universe. (Come by if you're in the UCR area. ETA: Or watch it live-streamed.) The speaker, Bahram Mobasher, has told me he likes to keep it tightly scientific -- no far-out speculations about the multiverse, no discussion of possible alien intelligences. Instead, we'll hear about H/He ratios, galactic formation, that sort of stuff. I have nothing to say about H/He ratios.
So here's what I'll say instead:
Alternatively, here’s a different way our universe might have begun: Someone might have designed a computer program. They might have put simulated agents in that computer program, and those simulated agents might be us. That is, we might be artificial intelligences inside an artificial environment created by some being who exists outside of our visible world. And this computer program that we are living in might have started ten years ago or ten million years ago or ten minutes ago.
This is called the Simulation Hypothesis. Maybe you’ve heard that Elon Musk, the famous tycoon of Paypal, Tesla, and SpaceX, believes that the Simulation Hypothesis is probably true.
Most of you probably think that Musk is wrong. Probably you think it vastly more likely that Professor Mobasher’s story is correct than that the Simulation Hypothesis is correct. Or maybe you think it’s somewhat more likely that Mobasher is correct.
My question is: What grounds this sense of relative likelihood? It’s doubtful that we can get definite scientific proof that we are not in a simulation. But does that mean that there are no rational constraints on what it’s more or less reasonable to guess about such matters? Are we left only with hard science on the one hand and rationally groundless faith on the other?
No, I think we can at least try to be rational about such things and let ourselves be moved to some extent by indirect or partial scientific evidence or plausibility considerations.
For example, we can study artificial intelligence. How easy or difficult is it to create artificial consciousness in simulated environments, at least in our universe? If it’s easy, that might tend to nudge up the reasonableness of the Simulation Hypothesis. If it’s hard, that might nudge it down.
Or we can look for direct evidence that we are in a designed computer program. For example, we can look for software glitches or programming notes from the designer. So far, this hasn’t panned out.
Here’s my bigger point. We all start with framework assumptions. Science starts with framework assumptions. Those assumptions might be reasonable, but they can also be questioned. And one place where cosmology intersects with philosophy and the other humanities and sciences is in trying to assess those framework assumptions, rather than simply leaving them unexamined or taking them on faith.
"1% Skepticism" (Nous, forthcoming)
"Reinstalling Eden" (with R. Scott Bakker; Nature, 2013)