On Tuesday, August 20, 2019 at 6:12:05 PM UTC-5, Bruce wrote: > > Bruno, > > I think it is clear that you have no coherent local causal many-worlds > account of the EPR correlations. If you did have one, you would have > produced it by now. Instead you keep changing the subject and propounding > irrelevant truisms as if they were great insights. > > So be it. I must admit that I am somewhat disappointed by this. Many > people casually claim that many-worlds solves the problem of non-locality, > but few even attempt to explain how this works. I thought that you might be > able to shed some light on the matter. If you could have done so, it would > have given some reason for taking the many-worlds ontology more seriously. > > As it stands, there would appear to be no reason for believing in the real > existence of the other worlds. One can then follow Zurek and use the > Everett insights into the primacy of unitary evolution of the wave > function, and the quantum basis for the classical world, to investigate how > the preferred basis is found (einselection); to investigate the origin of > probabilities and the Born rule (envariance); and to explain how the > objective classical world emerges from this unitary quantum substrate > (quantum Darwinism). As Zurek points out, once you can do this, the real > existence of these other worlds becomes irrelevant to physics, and one can > safely abandon them as superfluous mathematical superstructure. > > It seems that the last hope of finding a use for these other worlds as a > substitute for non-locality is now dead, and we are left with physics as it > always was -- a single classical world emerging from a quantum substrate. > There are many who will see this development as a relief from metaphysical > nonsense. > > Bruce >
I started reading this paper, but things got in the way --- including reading papers that are of more relevance to me. But --- but if I can I will try to read this before the week is out. This looks like some sort of PR box argument. MWI seems at first blush to be a nice way to avoid the apparent violence to QM that occurs with Bohr's CI. However, really it just remolds the problem into another shape. Since there appears to be no way to discern if any interpretation is empirically supported MWI in the end just might be a "it feels good" sort of argument. I wrote the following on Hossenfelder's blog recently: No matter how you look at it from a phenomenological perspective there is still a stochastic quantum jump, or what we call collapse. With Bohr and CI the replacement of a quantum state by a quantum basis state corresponding to a measured eigenvalue is considered to be axiomatic. With MWI there is this idea that on a deep quantum level there is no such violence committed, the world simply appears according to a local measurement by an observer who is in a sense "quantum frame dragged" along a reduced world based on that measured eigenvalue. From an empirical perspective there is no way to discern one from the other. They also both involve a sort of stochastic jump. If I have the time and temerity to jump into this cauldron of trouble, I may work out this conjecture I have this ultimately involves quantum states encoding quantum states. This runs into some incompleteness of Gödel's theorem. The implication is there is no decidable way to determine whether QM is ψ-epistemic, say in the sense of Bohr and Copenhagen Interpretation and Fuch's QuBism, or if it is ψ-ontic in the sense of MWI and GRW and ... . All of these have problems. Bohr and CI posit as fundamental quantum and classical domains. However as pointed out by Heisenberg early on there is an ambiguous boundary between these two domains. MWI proposes a splitting of worlds, but there is no definitive meaning to a spatial surface or set of them according to probabilities. Bohm's idea really only has sense in nonrelativistic domain, but that could hold for physics on a holographic screen, so while this has serious weaknesses I will not throw it completely under the bus. There are I read at last count over 50 interpretations. Collapses are not the result of unitary evolution and so appear inconsistent with the evolution of quantum states. I think this is some sort of incompleteness in the axioms or postulate of QM. It might be compared to the fifth axiom of Euclid in geometry. I think in the end, or if I am right, then this is simply a state of affairs that exists, there is no causal process behind it and we are best to just accept this and press on. Maybe this is Mermin's *Shut up and calculate* and this search for interpretations is a waste of time. LC -- 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 everything-list+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/everything-list/15101a72-fb2f-4be0-96ef-dd1a703f70a2%40googlegroups.com.
