So Mermin was on the right track, but he didn’t get it quite right: not only is the
moon is not really there when nobody looks, but it isn't really there even when
you do look! "Physical reality" is not "real", but information-theoretical reality is.
We are not physical entities, but informational ones. We are made of, to quote
Mermin, "correlations without correlata." We are not made of atoms, we are made
of (quantum) bits. At the risk of stretching a metaphor beyond its breaking point,
what we usually call reality is really a very high quality simulation running on a
quantum computer.
This is a very counterintuitive view of the world, but the mathematics of Quantum
Mechanics tell us unambiguously that it is correct, just as the mathematics of
relativity tell us that there is no absolute time and space. Entanglement, far from
being an obscure curiosity of QM, is in fact at its very heart. Entanglement is the
reason that measurement is possible, and thus the reason that the Universe is
comprehensible.
There is no quantum world. There is only an abstract physical description. It is wrong to think that the task of physics is to find out how nature is. Physics concerns what we can say about nature. Niels Bohr
Reality is not "running on a quantum computer" it is just that QM is the best description we have of what we can observe of the external world.
I'd be wary of it, I haven't read the whole thing but it seems suspicious, least of which is that he comes off as if he fully understands QM.
I only know so much about QM, but I do know that no one fully understands it, and that in attempting to sound deep, the author of this paper misattributed a classic Zen koan to Douglas Hofstadter.
That paper has been reviewed at one time or another by at least a dozen card-carrying physicists, including Jeff Kimble and John Preskill at Caltech (who are the ones who actually helped me figure all this stuff out). Reactions range from, "Oh my God, what a revelation!" to "Duh. Everybody already knows that." But I have yet to encounter anyone who knows what they're doing who thinks it's wrong.
"There's a widespread belief that quantum mechanics is supposed to be confusing. This is not a good frame of mind for either a teacher or a student. Complicated math can be difficult but it is never, ever allowed to be confusing."
I got it from GEB. Hofstadter doesn't attribute it, so I just assumed it was original with him. (And frankly I'd be surprised if you found any references to Zen Master Zeno prior to GEB.)
From the concluding section:
So Mermin was on the right track, but he didn’t get it quite right: not only is the moon is not really there when nobody looks, but it isn't really there even when you do look! "Physical reality" is not "real", but information-theoretical reality is. We are not physical entities, but informational ones. We are made of, to quote Mermin, "correlations without correlata." We are not made of atoms, we are made of (quantum) bits. At the risk of stretching a metaphor beyond its breaking point, what we usually call reality is really a very high quality simulation running on a quantum computer.
This is a very counterintuitive view of the world, but the mathematics of Quantum Mechanics tell us unambiguously that it is correct, just as the mathematics of relativity tell us that there is no absolute time and space. Entanglement, far from being an obscure curiosity of QM, is in fact at its very heart. Entanglement is the reason that measurement is possible, and thus the reason that the Universe is comprehensible.