On Thu, Feb 27, 2025 at 6:33 PM Brent Meeker <[email protected]> wrote:
*>> Towards Quantum Superpositions of a Mirror* >> <https://web.physics.ucsb.edu/~quopt/tow.pdf> > > > > *> That's to show that a macroscopic object can be in a superposition. I > don't see how that would test MWI?* > *Greg Egan asked: * *"I wonder just what the implications would be if the Bouwmeester et al. experiment* [*Towards Quantum Superpositions of a Mirror* <https://web.physics.ucsb.edu/~quopt/tow.pdf>] *shows no interference. It certainly gives an opportunity to falsify Penrose’s theory of gravitationally induced collapse, and a no-interference result would make that theory much more credible."* *Scott Aaronson responded: * "Yes, absolutely, there might be “gravity-induced environmental decoherence,” of a kind that left quantum-mechanical linearity formally intact. But even then, if the decoherence were irreversible for some fundamental reason (e.g., *if the differences in the gravitational metric in the two branches propagated outward at the speed of light, and the cosmology was such that the branches could never recohere*), then I’d tend to say that unitarity “remained on its throne only as a ceremonial monarch”! In other words,* as soon as we postulate any decoherence (whatever its source) that occurs below the level of everyday experience*, and that’s truly irreversible for fundamental physical reasons … at that point, I would say that *we can now fully explain our experience without any reference to parallel copies of ourselves in other branches*, and are therefore not forced into MWIism." *So in Scott Aaronson's opinion, the Bouwmeester experiment has the potential, at the very least, to make the MWI far less credible. That is probably why, despite Aaronson not being a big fan of MWI he is not a big critic either, he remains neutral on the issue. And I have never heard Aaronson say MWI is not a legitimate scientific idea because it is not falsifiable. * *So if you want we can argue about whether Aaronson is right or wrong about that, but you can't dispute that I was correct when I said that was Aaronson's opinion.* *John K Clark See what's on my new list at Extropolis <https://groups.google.com/g/extropolis>* *8b0* -- You received this message because you are subscribed to the Google Groups "Everything List" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion visit https://groups.google.com/d/msgid/everything-list/CAJPayv0MF3-mUuEfJvtC%3D%3DtDb2P1wMNto%2ByKp%2B4cmVBavySnsw%40mail.gmail.com.
