On Saturday, November 25, 2017 at 7:11:52 PM UTC, Lawrence Crowell wrote: > > On Saturday, November 25, 2017 at 11:55:47 AM UTC-6, [email protected] > wrote: >> >> >> >> On Saturday, November 25, 2017 at 3:06:50 PM UTC, Lawrence Crowell wrote: >>> >>> On Thursday, November 23, 2017 at 9:21:14 PM UTC-6, [email protected] >>> wrote: >>>> >>>> >>>> >>>> On Thursday, November 23, 2017 at 11:15:40 PM UTC, Lawrence Crowell >>>> wrote: >>>>> >>>>> >>>>> >>>>> I am new to this list and have not followed all the arguments here. In >>>>> weighing in here I might be making an error of not addressing things >>>>> properly. >>>>> >>>>> Consider quantum entanglements, say the entanglements of two spin 1/2 >>>>> particles. In the singlet state |+>|-> + |->|+> we really do not have the >>>>> two spin particles. The entanglement state is all that is identifiable. >>>>> The >>>>> degrees of freedom for the two spins are replaced with those of the >>>>> entanglement state. It really makes no sense to talk about the individual >>>>> spin particles existing. If the observer makes a measurement that results >>>>> in a measurement the entanglement state is "violently" lost, the >>>>> entanglement phase is transmitted to the needle states of the apparatus, >>>>> and the individual spin degrees of freedom replace the entanglement. >>>>> >>>>> We have some trouble understanding this, for the decoherence of the >>>>> entangled state occurs with that state as a "unit;" it is blind to any >>>>> idea >>>>> there is some "geography" associated with the individual spins. There in >>>>> fact really is no such thing as the individual spins. The loss of the >>>>> entangled state replaces that with the two spin states. Since there is no >>>>> "metric" specifying where the spins are before the measurement there is >>>>> no >>>>> sense to ideas of any causal action that ties the two resulting spins. >>>>> >>>>> This chaffs our idea of physical causality, but this is because we are >>>>> thinking in classical terms. There are two ways of thinking about our >>>>> problem with understanding whether quantum mechanics is ontic or >>>>> epistemic. >>>>> >>>> >>>> The fact that probability waves evolve and interfere with each other, >>>> and effect ensembles but not individual members, is inherently baffling. >>>> So >>>> the wf can't be completely epistemic since it modifies physical reality. >>>> That is, It must be ontic in some respect, but in ways that defy rational >>>> analysis. AG >>>> >>> >>> I think you are falling into a trap that David Hume warns against. >>> Causality gives rise to correlation, but correlation is not necessarily the >>> result of causality. There is no effect or some causal principle at work >>> with either individual wave functions or wave functions in an ensemble of >>> experiments. The ensemble of experiments, the classic case being the two >>> slit experiment, is meant to deduces the wave nature of the quantum >>> physics. It is not there to deduce some causal influence underlying quantum >>> nonlocality. >>> >>> LC >>> >> >> Applying deBroglie's formula, a change in p changes the wave length, and >> thus the distribution on the screen. That is, the ensemble responds to >> changes in the wave length due to interference. I therefore deduce that the >> wave length has a physical effect on the ensemble, but not on individual >> outcomes. AG >> > > You continue to make the error of thinking there must be some physical > effect in a measurement. >
In a particular measurement outcome? expressly denied that. I stated the physical effect of the wf is only discernible for ensembles. AG The outcomes will obey a statistical distribution that is reflected in an > ensemble of experiments. The statistical distribution is predicted by the > nature of the wave function prior to a measurement. The wave function can > be interpreted in a ψ-epistemic sense (Copenhagen, Qubism etc) as only > telling you what information can be accessed from the quantum system. In a > ψ-ontic sense (MWI, Bohm etc) the wave function exists and evolves to > define possible outcomes, but the observer is not able to access any > predictive information as this necessitates some local hidden variable that > does not exist. What outcome happens in any particular measurements is not > predictable; there exists no causal principle which can tell you how a > particular outcome obtains. > I never alleged otherwise. AG > The occurrence of a statistical distribution of outcomes from an ensemble > of measurements does not mean there is some causal influence directing > outcomes. > If the ensemble's distribution changes as a consequence of changes in the wf, IMO there is reason to believe the wf has ontic properties. That's all I was alleging. AG > This distribution only obtains as a consequence of what the wave function > tells you (ψ-epistemology) about the system before measurement, or how the > wave function evolves as a physical system (ψ-ontology) prior to > measurement. It is my thinking that QM fails to completely live up to > either of these. > > 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 [email protected]. To post to this group, send email to [email protected]. Visit this group at https://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.
