On Wed, Dec 11, 2013 at 2:39 PM, meekerdb <meeke...@verizon.net> wrote:
> On 12/11/2013 2:07 AM, Jason Resch wrote: > > > > > On Wed, Dec 11, 2013 at 1:32 AM, meekerdb <meeke...@verizon.net> wrote: > >> On 12/10/2013 10:47 PM, Jason Resch wrote: >> >> >> >> >> On Wed, Dec 11, 2013 at 12:19 AM, meekerdb <meeke...@verizon.net> wrote: >> >>> On 12/10/2013 9:49 PM, Jason Resch wrote: >>> >>> >>> >>> >>> On Tue, Dec 10, 2013 at 9:53 PM, meekerdb <meeke...@verizon.net> wrote: >>> >>>> On 12/10/2013 5:23 PM, LizR wrote: >>>> >>>> On 10 December 2013 09:06, Jason Resch <jasonre...@gmail.com> wrote: >>>> >>>>> >>>>> Bell's theorm proves that local hidden variables are impossible >>>>> which leaves only two remaining explanations that explain the EPR paradox: >>>>> >>>>> 1. Non-local, faster-than-light, relativity violating effects >>>>> 2. Measurements have more than one outcome >>>>> >>>>> In light of Bell's theorem, either special relativity is false or >>>>> many-world's is true. >>>>> >>>>> Bell realised there was a third explanation involving the relevant >>>> laws of physics operating in a time symmetric fashion. (Oddly this appears >>>> to be the hardest one for people to grasp, however.) >>>> >>>> >>>> Yes, that idea has been popularized by Vic Stenger and by Cramer's >>>> transactional interpretation. >>>> >>> >>> Collapse is still fundamentally real in the transactional >>> interpretation, it is just even less clear about when it occurs. The >>> transactional interpretation is also non-local, non-deterministic, and >>> postulates new things outside of standard QM. >>> >>> >>> I think it's still local, no FTL except via zig-zags like Stenger's. >>> >>> >>> >>> >> This table should be updated in that case: >> https://en.wikipedia.org/wiki/Interpretations_of_quantum_mechanics#Comparison_of_interpretations >> >> >> Hmm. I think the transactional waves are not FTL but in an EPR >> experiment would relay on backward-in-time signaling. Not sure why it says >> TIQ is explicitly non-local? >> >> > > I don't know enough about TIQM to say, but the wikipedia article on it > also mentions in several places that it is explicitly non-local: > > http://en.wikipedia.org/wiki/Transactional_interpretation > > > > >> >> What are the zig-zags? >> >> >> By "traveling" back in time and then forward a particle can be at two >> spacelike separate events. >> >> >> > Is it the Feynman Stueckelberg interpretation of antimatter? In that > the positron and electron created in the decay of a particle can be > envisioned as the same particle, with the positron travelling backwards in > time. In the case of that anti-matter interpretation, neither is FTL. > > > Right. So it's "local" in the sense of slower than light, although it > effectively implements a non-local hidden variable. > > That is a rather neat trick. I like it. However, I still find MWI more plausible for the other reasons I provided. > > > >> >> >>> >>> Why? Everett showed the Schrodinger equation is sufficient to explain >>> all observations in QM. >>> >>> >>> But it's non-local too. If spacelike measurement choices in are made >>> in repeated EPR measurements the results can still show correlations >>> violating Bell's inequality - in the same world. >>> >> >> Can you explain the experimental setup where this happens? >> >> >> http://arxiv.org/abs/quant-ph/9810080 >> >> >> > Isn't that the ordinary EPR paradox with Bell's extension to disprove > local hidden variables? I don't see how this shows anything contrary to > predictions of QM / Everett. As I mentioned earlier, Bell's Theorem only > disproves local hidden variables. It leaves two possible alternatives: > FTL/non-local influences and measurements with more than one outcome. > > > When they measure the same attribute, the result is correlated as I > described before, leading to two worlds. When they measure the uncorrelated > observables, each is split separately when they make the measurement, and > then the split spreads at light speed to the other, creating four > superposed states. > > > But the measurements with more than one outcome turn out to be more > correlated than allowed by classical mechanics. > Bell's inequality doesn't apply when more than one outcome is possible. You can treat them as "non-hidden, (since they are in the equation) correlated, multi-valued variables". Bell's inequality cannot be addressed with local (non-interacting) single-outcome variables, because once you measure one, to agree with QM it must instantly affect the other to explain the outcome of the remote measurement. If you assume there cannot be this action at a distance, and that there are hidden deterministic state tables that define the outcome of the measurement, this is what Bell's inequality shows cannot be made to agree with QM. In QM, when you send the two entangled photons to two remote polarization filters, which are offset by 30 degrees, you will find that they agree 75% of the time. Which is exactly the result you get whenever you send light of a known polarization through a filter offset at 30 degrees from that base: 75% of the light makes it through. That the light that makes it through is cos(d)^2 where d is the difference in angle, is itself not a violation of Bell's inequalities, what makes it a violation is supposing that a single-valued variable can contain the information necessary such that: for any randomly chosen rotation of angle *X* for the polarizing filter at Earth, to agree 75% of the time with another filter at Proxima Centauri, also randomly chosen but just happening to be selected to equal* X+30 degrees* while at the same time, agreeing 100% of the time when the angles are randomly selected and are the same at Earth and Proxima Centauri. What does explain it, without non-localism is to suppose that each photon is in a superposed state of all possible polarizations, and further that there is an existing one-to-one correspondence between each of the superposed states for one photon and the entangled other photon. E.g., (p0 x p180) + (p1 x p181) + (p2 x p182) ... (p179 x p359) + (p180 x p0) + (p181 x p1) ... (p358 x p178) + (p359 x p179). Each photon is in all the states, and when you measure one of them, you become part of that superposition (in this case 360 different superposed states), and each corresponds to one of the results for the other remote photon. However, the photons traveled at c to get where they are, and the spreading of the superposition after measurement also spreads at c or slower into the environment. > So the four outcomes are not equally probable, in spite of the symmetry of > the experiment. > That's just a property of how photons of certain polarizations behave when they go through polarizers that are offset from their polarization. > That's why it implies non-locality in any hidden variable model. > I think you are confusing the implications of Bell's theorem. It disproves hidden variables (with a single value) that do not have some non-local causal impact on each other when the other is measured. > I don't see that multiple worlds makes the non-locality go away, it just > seems to rephrase it in terms of some worlds interfering more than others. > > There is no interference among worlds. Interference can only happen when there are no surviving records (including any misplaced particles) between two states in a superposition. In other words, to restore the system to a state where interference can happen, all the particles need to be put back where they would have been (or otherwise in the same way) regardless of what the outcome of the measurement was. If this isn't done, there will be no interference. > > > >> >> >> >>> The Schrodinger equation has solutions in Hilbert space, which are not >>> local in spacetime. >>> >>> >> Are you referring to momentum vs. position basis ( >> http://lesswrong.com/lw/pr/which_basis_is_more_fundamental/ ) or >> something else? >> >> >> No, just that a ray in Hilbert space, a state, corresponds to a solution >> of the SWE over configuration space (with boundary conditions) which in >> general is not localized in spacetime. >> > > Locality (as I've used the term) refers to the idea that things are only > affected by their immediate environment. I think you are speaking of > something else when you speak of being able to locate it somewhere in > space-time. > > > > If a wave function extends over a large region, then a local interaction > with it here affects it's value over there. > I don't see how it effects the value. Any entangled pair of particles have "measured each other", and together remain in a superposition of all possible states. When you measure one of the pair, you get a result, and since that particle measured the other, you know the other one's value too. > That's why a choice of measurement polarization at one end of an EPR > affects the results observed at the other end, even when the two are > spacelike. > > > It's not you or your measurement that changes the state of the particles. This is a backwards way of looking at it. It is the state of the particles that when measured, changes the state of you. It puts you and your particles into a superposition. Consider a photon that passes through a pane of glass, such that it is both reflected and transmitted. Essentially, its position and direction are multi-valued properties. If one of the paths of the photon is aimed at an electron, then the interaction of this multi-position photon will both hit and miss the electron. The electron is then deflected and not deflected by the hit and miss, and so the electron is in two states, having two positions and directions. So from this simple example, you can see clearly how superposition spreads, and how correlations are preserved. The deflected electron is correlated to the photon that hit it, which is correlated to the photon that reflected. While the stationary electron is correlated with the photon that missed it, which was transmitted through the glass. If the electron that was hit by the photon hits a TV screen, then the TV screen in the state of emitting light is correlated with the deflected electron, etc., and the dark TV screen is correlated with the stationary electron. If a person sees the TV flash, he too is put into a state of having seen and not having seen the TV screen flash, and so this single photon, put into two positions by a piece of glass, has led to two independent states of all the particles in the human observer. Does this make sense? Jason > > > >> >> >> >> >>> >>> Is it just so people can sleep soundly at night believing the >>> universe is small and that they are unique? >>> >>> >>>> There's also hyperdeterminism in which the experimenters only *thinks* >>>> the can make independent choices. t'Hooft tries to develop that viewpoint. >>>> >>> >>> Hyper-determinism sounds incompatible with normal determinism, as it >>> seems to imply a the deterministic process of an operating mind is forced >>> (against its will in some cases), to decide certain choices which would be >>> determined by something operating external to that mind. >>> >>> I think I can use the pigeon hole principle to prove hyper-determinism >>> is inconsistent with QM. Consider an observer whose mind is represented by >>> a computer program running on a computer with a total memory capacity >>> limited to N bits. Then have this observer make 2^n + 1 quantum >>> measurements. If hyperdeterminism is true, and the results matches what the >>> observer decided to choose, then the hyper-determistic effects must be >>> repeating an on interval of 2^n or less. >>> >>> >>> There's nothing in the theory to limit the capacity to local memory, if >>> hyper-determinism is true, it's true of the universe as a whole. >>> >> >> What if we have two remote locations measuring entangled particles, and >> whether they measure the x-spin or y-spin for the i-th particle depends on >> the i-th binary digit of Pi at one locations, and the i-th binary digit of >> Euler's constant at the other location? How can hyper-determinism force >> the digits of Pi or e? >> >> >> ?? I think the i-th digit pi and the i-th digit of e are already >> determined. >> >> > Yes, but they are determined by math, not this hyper-determinism concept > which I understand is a hypothesized physical process. > > > I'm not even sure what a "physical" process would mean in this context. > It's determined by the way the universe is, like 2+2 is determined to be 4. > > > > You said hyperdeterminism means experimenters only think they can make > independent choices, but what if an experimenter chooses to rely on the > digits of some constant number to inform his or her choices in the > experiment? Does hyper-determinism decide not only that the experimenter > chooses to use Pi, but also each of the resulting steps the experimenter > makes when using Pi as his/her guide? > > > Right. That's why it's *hyper*-determinism. > > 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-list+unsubscr...@googlegroups.com. > To post to this group, send email to everything-list@googlegroups.com. > Visit this group at http://groups.google.com/group/everything-list. > For more options, visit https://groups.google.com/groups/opt_out. > -- 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 post to this group, send email to everything-list@googlegroups.com. Visit this group at http://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/groups/opt_out.
