On Sunday, June 9, 2019 at 11:52:02 PM UTC-5, Bruce wrote: > > On Wed, Jun 5, 2019 at 11:25 PM Philip Thrift <[email protected] > <javascript:>> wrote: > >> On Wednesday, June 5, 2019 at 7:56:41 AM UTC-5, Philip Thrift wrote: >>> >>> On Wednesday, June 5, 2019 at 6:45:32 AM UTC-5, Lawrence Crowell wrote: >>>> >>>> On Tuesday, June 4, 2019 at 10:22:51 PM UTC-5, Bruce wrote: >>>>> >>>>> On Wed, Jun 5, 2019 at 1:15 PM Philip Thrift <[email protected]> >>>>> wrote: >>>>> >>>>>> >>>>>> As for quantum stochastic retrodependency (which physicists avoid >>>>>> like vampires avoid sunlight), it simplifies the "puzzles" of QM, >>>>>> meaning >>>>>> that, for the most part, the articles you see talking about the "spooky >>>>>> action at a distance" or "many wolds" of QM you can dump in the trashcan >>>>>> and save a lot of time! >>>>>> >>>>> >>>>> The trouble is that these retrocausal "explanations" do not actually >>>>> explain anything! They sound like they should: "The formation of the EPR >>>>> pair depends on the future setting of the polarises as well as on the >>>>> state >>>>> preparation." (Or something similar). But no detailed dynamics are ever >>>>> given, and the supposed explanation is even more mystical than "spooky >>>>> action at a distance...." >>>>> >>>>> Bruce >>>>> >>>> >>>> Bingo --- ting ding ting ding ... . Thanks Bruce. Since QM is time >>>> symmetric or invariant in its form with respect to time direction whether >>>> you define time forwards or backwards, or do so for some partition of a >>>> density matrix or wave, makes no difference. Retrocausality in effect >>>> solves nothing. Nonlocality and the contextual nature of QM, eg the >>>> Mermin-Peres square that gives Kochen-Specker, have no definition with >>>> respect to any time direction. If you have locality in QM then it is still >>>> not possible to think meaningfully of counterfactual definiteness (CFD), >>>> or >>>> if QM is regarded as nonlocal only then can you have CFD, such as with >>>> Many >>>> Worlds Interpretation. It makes no difference whether the observables >>>> measured are considered forwards or backwards evolving. >>>> >>>> LC >>>> >>> >>> >>> Retrocausality in effect solves nothing. >>> >>> It solves wasting any time reading papers about QM many worlds, >>> non-locality, all the nonsense you read today. >>> >>> [If one views QM as a generalized measure on a space of histories, then >>> one sees not only how quantal processes differ from classical stochastic >>> processes (the main difference, they satisfy different sum rules), but also >>> how closely the two resemble each other.] >>> via Rafael Sorkin >>> >>> @philipthrift >>> >> >> >> Anyway, as you know well, I "adopted" the retrocausal view 20 years ago >> via* Victor J. Stenger,* who pointed of course to Huw Price. >> > > > Apart from not solving anything, and the problem of the absence of any > dynamical explanation as to how retrocausality might work to eliminate > non-locality, the real problem is that retrocausal explanations have been > ruled out experimentally. > > The seminal experiment by Aspect, et al., published in 1982 really put the > last nail in the coffin of retrocausal explanations. The point is that in > Aspect's experiment, the polariser settings were chosen while the photons > were in flight -- in other words, at some time after the singlet pair was > created. So there is no way the photons, travelling back in time at the > speed of light, could ever reach the original singlet state after they had > detected the polariser setting. The best they could do would be to carry > the polariser setting back half way, but no way could they reach back to > the interaction that created the original singlet state. > > So all these years, Huw Price and his cronies have been talking absolute > rubbish -- their theory has already been falsified by experiment. > > Bruce >
Rubbish. A complete misunderstanding of quantum mechanics. Retrocausal hidden variable models are completely compatible with experiments, unless QM itself is wrong. @philipthrift -- 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 on the web visit https://groups.google.com/d/msgid/everything-list/ebfb90f2-b112-4b65-9505-26e5283d32de%40googlegroups.com.
