Interesting that TI might show this. Q-interpretations can have their utility.

LC On Sunday, October 30, 2022 at 8:27:56 PM UTC-5 meeke...@gmail.com wrote: > Thanks. I found this critique by Kastner (who of course says that the > transactional interpretation solves the problem). > > https://arxiv.org/ftp/arxiv/papers/1308/1308.4272.pdf > > Brent > > > > On 10/30/2022 4:41 PM, Lawrence Crowell wrote: > > I remember some issue surrounding this. I do not remember the way it was > resolved, but I do recall that Hobson was considered wrong. > > LC > > On Saturday, October 29, 2022 at 8:04:35 PM UTC-5 meeke...@gmail.com > wrote: > >> >> >> On 10/29/2022 6:29 AM, Lawrence Crowell wrote: >> >> On Friday, October 28, 2022 at 10:55:50 PM UTC-5 Bruce wrote: >> >>> On Sat, Oct 29, 2022 at 1:42 PM Brent Meeker <meeke...@gmail.com> wrote: >>> >>>> >>>> On 10/28/2022 6:43 PM, Bruce Kellett wrote: >>>> >>>> Look, "ad hoc" is frequently bandied about as a fatal flaw in any >>>> theory. Just as Putin waves about the nuclear threat: this is just to >>>> intimidate the opposition, it doesn't mean anything more. Any theory has >>>> ad >>>> hoc elements, or else it would not be of any value in explaining our >>>> experience. There is always a theoretical part, and then a collection of >>>> elements that serve to relate the theory to observation. Everything is >>>> ultimately ad hoc, because it is for the particular purpose of explaining >>>> observation. >>>> >>>> >>>> I think you've stretched it's meaning beyond recognition. If every >>>> theory that is devised to match experiment is ad hoc then indeed all >>>> science is ad hoc...and the better for it. But there is real ad hockery >>>> that is deserving of criticism. >>>> >>>> The real question on the table is what would you take to be not ad hoc; >>>> what would be better than "... measurement is then not treated in terms of >>>> the fundamental dynamics of the theory." Do you see MWI doing this? >>>> >>> >>> No. MWI takes unitary dynamics of the Schrodinger equation to be >>> fundamental. But unitary dynamics and the SE are deterministic, and >>> incompatible with a probabilistic interpretation. So MWI is not going to be >>> able to give a completely satisfactory account of measurement since the >>> outcomes of measurement are inherently probabilistic. So whatever you do in >>> MWI, measurement is not treated in terms of the fundamental dynamics of the >>> theory; there is always some ad hoc element required to make contact with >>> experiment. In that context MWI, is simply engaging in a double standard >>> when it criticizes collapse theories as ad hoc. >>> >>> Bruce >>> >> >> Quantum mechanics deals with the evolution of probability amplitudes a_i >> and probabilities are p_i = |a_i|^2. The probabilities are the trace of the >> density matrix and the density matrix by the Schrodinger equation is dρ/dt >> = [H, ρ], and this describes the evolution of probabilities. With an actual >> outcome the probabilities are no longer applicable due to there being only >> one outcome. >> >> LC >> >> >> Art Hobson has a series of papers on the "measurement problem" in which >> he argues that past analyses, by von Neumann and others, incorrectly ignore >> non-local entanglement in going from the density matrix of the >> system+instrument to the diagonalized system+instrument representing a >> mixture. And when this is correctly accounted for he says the non-local >> entanglement causes the measured value (which is random per Born) to be a >> unique realization of the eigenvector...no multiple worlds. >> >> SUMMARY AND CONCLUSION >> Using only the standard principles of quantum physics, but minus the >> collapse postulate, we have shown that quantum state collapse occurs as a >> consequence of the entanglement that occurs upon measurement as described >> in >> 1932 by von Neumann (Equation (4)). The entangled "measurement state" of a >> quantum system and its detector is the collapsed state: It incorporates >> the required >> perfect correlations between the system and its detector, it predicts >> precisely one >> definite outcome, and it incorporates the nonlocal properties--the >> instantaneous >> collapse across all branches of the superposition--that Einstein showed >> to be >> required in quantum measurements >> >> See attached. >> >> Brent >> > -- > > 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-li...@googlegroups.com. > > To view this discussion on the web visit > https://groups.google.com/d/msgid/everything-list/22de4eaa-94a7-4d2a-99f0-a09cba1634cbn%40googlegroups.com > > <https://groups.google.com/d/msgid/everything-list/22de4eaa-94a7-4d2a-99f0-a09cba1634cbn%40googlegroups.com?utm_medium=email&utm_source=footer> > . > > > -- You received this message because you are subscribed to the Google Groups "Everything List" group. 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