[dotsam]

David Deutsch opposes this view in his 'It from Qubit': https://www.daviddeutsch.org.uk/wp-content/ItFromQubit.pdf

> [the view Deutsch opposes] entails giving up on explanation in science. It is in the very nature of computational universality that if we and our world were composed of software, we should have no means of understanding the real physics – the physics underlying the hardware of the Great Simulator itself. Of course, no one can prove that we are not software. Like all conspiracy theories, this one is untestable. But if we are to adopt the methodology of believing such theories, we may as well save ourselves the trouble of all that algebra and all those experiments, and go back to explaining the world in terms of the sex lives of Greek gods.

...

> these approaches fail because they attempt to reverse the direction of the explanations that the real connections between physics and computation provide. They seem plausible only because they rely on a common misconception about the status of computation within mathematics. The misconception is that the set of computable functions (or the set of quantum-computational tasks) has some a priori privileged status within mathematics. But it does not. The only thing that privileges that set of operations is that it is instantiated in the computationally universal laws of physics. It is only through our knowledge of physics that we know of the distinction between computable and non-computable (see Deutsch, Ekert and Luppaccini 2000), or between simple and complex.

There's a related video here: https://www.youtube.com/watch?v=UohR3OXzXA8

And more on what he calls the Mathematicians’ Misconception: https://www.daviddeutsch.org.uk/wp-content/uploads/2018/03/M...

Incidentally, Wheeler was his boss at one stage.

[titzer]

What Deutsch is saying is that any simulation is going to virtualize all possible observations (including time and any/all side channels), which means there's no way to see through the abstraction.

But that doesn't mean we are in a simulation (i.e. are software). It'd be actually kind of dumb if we were, as this universe cannot be simulated efficiently on classical computers--the kind that occur to logicians working from the first principles of mathematics. Our universe wasn't designed by a CS person, that's for sure.