Re: Entanglement
On 4/20/2018 6:43 AM, agrayson2...@gmail.com wrote: No, what Bruno wrote was "a superposition of "Iup>IMinus> and (Minus>Iup>", which I took to mean an attempt to expand the singlet state in two bases simultaneuosly -- the (|Plus>, |Minus>) base and the (|up>,|down>) base. It is difficult to see exactly what this would achieve; it seems to be merely a more complicated base. Bruce I think by |minus> he just meant |dn>. AG If that's what he did, he's responsible for a lot of confusion. :-) 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 https://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.
Re: What is a Löbian machine/number/combinator
I never got past the first line of Bruno’s post because he said: "*Consider any Turing universal machinery, for example the programming language c++*” C++ is Turing complete but is not a Turing machine because machines are physical objects made of atoms but C++ is not nor is any language. As for Löbian machines that is yet another term that Bruno made up and is seen on this list but nowhere else. And Turing explained exactly precisely how to make one of his machines in the real physical world but Bruno has no idea how to even start to build one of his machines, which means he doesn’t understand how it works or even exactly what it is he’s talking about. John K Clark -- 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 https://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.
Re: Entanglement
On Friday, April 20, 2018 at 3:37:48 PM UTC, agrays...@gmail.com wrote: > > > > On Friday, April 20, 2018 at 2:54:25 PM UTC, agrays...@gmail.com wrote: >> >> >> >> On Friday, April 20, 2018 at 12:00:25 PM UTC, Bruce wrote: >>> >>> From: >>> >>> >>> >>> *Does entanglement -- which occurs whenever two systems interact -- >>> imply non-locality? AG* >>> >>> >>> Not necessarily. If there is a common cause explanation of the >>> correlation, as in classical physics where particles always have definite >>> momenta, then there is no need for a non-local explanation. >>> >> > I forget. In classical elastic scattering of two particles, do the > outgoing particles have definite momenta, equal and opposite of the > incoming particles, or what? > Sorry; that result is just for direct impacts. If not direct, IIRC the equations of motions yield definite results for the outgoing particles. CMIIAW. AG > In the quantum treatment, defined by including uncertainty in momenta, > does non locality arise due to inherent nature of the WF, which is a > superposition where the states of the subsystems (the two particles) are > indeterminate prior to measurement? AG > > >> However, in quantum systems such as the singlet state of entangled >>> spinors, then no common cause or hidden variable explanation is available >>> and we have non-locality. >>> >>> Actually a similar thing happens in any collision between two quantum >>> particles. If we assume an elastic collision, the outgoing particles will >>> be in the form of outgoing spherical waves -- neither the individual >>> momenta or directions are specified by the collision itself. So observing >>> the direction and/or momentum of one particle determines the direction and >>> momentum of the other remote particle. There is no common cause or hidden >>> variable explanation available for this, especially if the observations are >>> at space-like separations. However, as far as I know there are no Bell-like >>> inequalities that are violated by the statistics in this case, >>> >> >> Shouldn't there be such violations? AG >> >> >>> so the non-locality is not always obvious. Interestingly, this forms the >>> basis for an important measurement tool at high energy accelerators. Often >>> the output from experiments will be in the form of a missing mass plot, >>> which is constructed by summing the momenta of the observed particles and >>> determining what is missing. This can then be the basis of a search for >>> undetectable or new particles. >>> >>> Bruce >>> >> -- 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 https://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.
Re: Entanglement
On Friday, April 20, 2018 at 2:54:25 PM UTC, agrays...@gmail.com wrote: > > > > On Friday, April 20, 2018 at 12:00:25 PM UTC, Bruce wrote: >> >> From: >> >> >> >> *Does entanglement -- which occurs whenever two systems interact -- imply >> non-locality? AG* >> >> >> Not necessarily. If there is a common cause explanation of the >> correlation, as in classical physics where particles always have definite >> momenta, then there is no need for a non-local explanation. >> > I forget. In classical elastic scattering of two particles, do the outgoing particles have definite momenta, equal and opposite of the incoming particles, or what? In the quantum treatment, defined by including uncertainty in momenta, does non locality arise due to inherent nature of the WF, which is a superposition where the states of the subsystems (the two particles) are indeterminate prior to measurement? AG > However, in quantum systems such as the singlet state of entangled >> spinors, then no common cause or hidden variable explanation is available >> and we have non-locality. >> >> Actually a similar thing happens in any collision between two quantum >> particles. If we assume an elastic collision, the outgoing particles will >> be in the form of outgoing spherical waves -- neither the individual >> momenta or directions are specified by the collision itself. So observing >> the direction and/or momentum of one particle determines the direction and >> momentum of the other remote particle. There is no common cause or hidden >> variable explanation available for this, especially if the observations are >> at space-like separations. However, as far as I know there are no Bell-like >> inequalities that are violated by the statistics in this case, >> > > Shouldn't there be such violations? AG > > >> so the non-locality is not always obvious. Interestingly, this forms the >> basis for an important measurement tool at high energy accelerators. Often >> the output from experiments will be in the form of a missing mass plot, >> which is constructed by summing the momenta of the observed particles and >> determining what is missing. This can then be the basis of a search for >> undetectable or new particles. >> >> Bruce >> > -- 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 https://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.
Re: Entanglement
On Friday, April 20, 2018 at 12:00:25 PM UTC, Bruce wrote: > > From: > > > > > *Does entanglement -- which occurs whenever two systems interact -- imply > non-locality? AG* > > > Not necessarily. If there is a common cause explanation of the > correlation, as in classical physics where particles always have definite > momenta, then there is no need for a non-local explanation. However, in > quantum systems such as the singlet state of entangled spinors, then no > common cause or hidden variable explanation is available and we have > non-locality. > > Actually a similar thing happens in any collision between two quantum > particles. If we assume an elastic collision, the outgoing particles will > be in the form of outgoing spherical waves -- neither the individual > momenta or directions are specified by the collision itself. So observing > the direction and/or momentum of one particle determines the direction and > momentum of the other remote particle. There is no common cause or hidden > variable explanation available for this, especially if the observations are > at space-like separations. However, as far as I know there are no Bell-like > inequalities that are violated by the statistics in this case, > Shouldn't there be such violations? AG > so the non-locality is not always obvious. Interestingly, this forms the > basis for an important measurement tool at high energy accelerators. Often > the output from experiments will be in the form of a missing mass plot, > which is constructed by summing the momenta of the observed particles and > determining what is missing. This can then be the basis of a search for > undetectable or new particles. > > Bruce > -- 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 https://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.
Re: Entanglement
On Friday, April 20, 2018 at 1:04:05 PM UTC, Lawrence Crowell wrote: > > On Friday, April 20, 2018 at 7:00:25 AM UTC-5, Bruce wrote: >> >> From: >> >> >> >> *Does entanglement -- which occurs whenever two systems interact -- imply >> non-locality? AG* >> >> >> Not necessarily. If there is a common cause explanation of the >> correlation, as in classical physics where particles always have definite >> momenta, then there is no need for a non-local explanation. However, in >> quantum systems such as the singlet state of entangled spinors, then no >> common cause or hidden variable explanation is available and we have >> non-locality. >> >> Actually a similar thing happens in any collision between two quantum >> particles. If we assume an elastic collision, the outgoing particles will >> be in the form of outgoing spherical waves -- neither the individual >> momenta or directions are specified by the collision itself. So observing >> the direction and/or momentum of one particle determines the direction and >> momentum of the other remote particle. There is no common cause or hidden >> variable explanation available for this, especially if the observations are >> at space-like separations. However, as far as I know there are no Bell-like >> inequalities that are violated by the statistics in this case, so the >> non-locality is not always obvious. Interestingly, this forms the basis for >> an important measurement tool at high energy accelerators. Often the output >> from experiments will be in the form of a missing mass plot, which is >> constructed by summing the momenta of the observed particles and >> determining what is missing. This can then be the basis of a search for >> undetectable or new particles. >> >> Bruce >> > > There is an open question about this. The role of interactions is not > entirely clear. For instance, if we have a proton on proton collision that > produces as Z particle, the decay products of the Z, ultimately for > instance it might be a pair of photons, are entangled. The role of > interactions and the relationship between gauge symmetries and the quotient > group structure of entanglements is an interesting topic. > > It does have to be pointed out that in QFT with equal time commutators of > operators on spatial surfaces the nonlocality of QM is swept under the rug. > Since these nonlocal physics will only be apparent over a tiny distance > compared to the scale of the detector this loss is not considered terrible. > This eliminates nonlocality as some confusion with causal propagation, > which BTW happens with the Bohm relativistic QM. > > LC > I thought one of the main insufficiencies with Bohm QM is that it can't be made relativistic. AG -- 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 https://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.
Re: Entanglement
On Friday, April 20, 2018 at 11:40:13 AM UTC, Bruce wrote: > > From: > > > On Friday, April 20, 2018 at 1:18:32 AM UTC, Bruce wrote: >> >> From: Bruno Marchal >> >> On 18 Apr 2018, at 15:45, Bruce Kellett wrote: >> >> From: Bruno Marchal >> >> On 17 Apr 2018, at 13:52, Bruce Kellett wrote >> >> >> But note particularly that the spin measurement is made in the basis >> chosen by the experimenter (by orienting his/her magnet). >> >> >> OK. >> >> The outcome of the measurement is + or -, >> >> >> For Alice and Bob, OK. >> >> not one of the possible infinite set of possible basis vector >> orientations. The orientation is not measured, it is chose by the >> experimenter. So that is one potential source of an infinite set of worlds >> eliminated right away. The singlet is a superposition of two states, + and >> -: it is not a superposition of possible basis vectors. >> >> >> ? (That is far too ambiguous). >> >> >> ? It is not in the least ambiguous. The singlet state is not a >> superposition of basis vectors. >> >> > Actually, to clarify, I meant a superposition of vectors from different > bases. > > >> ? >> >> The singlet state is the superposition of Iup>IMinus> and (Minus>Iup>. >> >> >> Those are not generalized basis vectors: they are eigenfunctions of the >> spin projection operator in a particular basis. The singlet state is not a >> superposition of vectors from different bases. >> > > *Bruce; I found your above comment confusing and it led to subsequent > questions that LC found inappropriately technical or detailed for this > forum (which it isn't IMO). Why do you bring in superpositions from > different bases? I never saw that used in QM texts.* > > > No, you wouldn't see it in QM texts because it is not something that one > would usually do, because, as Brent and I discussed, it is rather > pointless. Any vector in the Hilbert space can be expressed as a linear > superposition of basis vectors, and the basis vectors in any basis are just > further vectors in the space, after all. So expanding in multiple bases can > always be reduced to an expansion in a single base. Which base is > immaterial. > > *Additionally, isn't Bruno correct that the above expression for the > singlet state which your earlier wrote down, IS a superposition in the > UP/DN basis? AG* > > > No, what Bruno wrote was "a superposition of "Iup>IMinus> and > (Minus>Iup>", which I took to mean an attempt to expand the singlet state > in two bases simultaneuosly -- the (|Plus>, |Minus>) base and the > (|up>,|down>) base. It is difficult to see exactly what this would achieve; > it seems to be merely a more complicated base. > > Bruce > I think by |minus> he just meant |dn>. AG -- 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 https://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.
Re: Entanglement
On Friday, April 20, 2018 at 7:00:25 AM UTC-5, Bruce wrote: > > From: > > > > > *Does entanglement -- which occurs whenever two systems interact -- imply > non-locality? AG* > > > Not necessarily. If there is a common cause explanation of the > correlation, as in classical physics where particles always have definite > momenta, then there is no need for a non-local explanation. However, in > quantum systems such as the singlet state of entangled spinors, then no > common cause or hidden variable explanation is available and we have > non-locality. > > Actually a similar thing happens in any collision between two quantum > particles. If we assume an elastic collision, the outgoing particles will > be in the form of outgoing spherical waves -- neither the individual > momenta or directions are specified by the collision itself. So observing > the direction and/or momentum of one particle determines the direction and > momentum of the other remote particle. There is no common cause or hidden > variable explanation available for this, especially if the observations are > at space-like separations. However, as far as I know there are no Bell-like > inequalities that are violated by the statistics in this case, so the > non-locality is not always obvious. Interestingly, this forms the basis for > an important measurement tool at high energy accelerators. Often the output > from experiments will be in the form of a missing mass plot, which is > constructed by summing the momenta of the observed particles and > determining what is missing. This can then be the basis of a search for > undetectable or new particles. > > Bruce > There is an open question about this. The role of interactions is not entirely clear. For instance, if we have a proton on proton collision that produces as Z particle, the decay products of the Z, ultimately for instance it might be a pair of photons, are entangled. The role of interactions and the relationship between gauge symmetries and the quotient group structure of entanglements is an interesting topic. It does have to be pointed out that in QFT with equal time commutators of operators on spatial surfaces the nonlocality of QM is swept under the rug. Since these nonlocal physics will only be apparent over a tiny distance compared to the scale of the detector this loss is not considered terrible. This eliminates nonlocality as some confusion with causal propagation, which BTW happens with the Bohm relativistic QM. 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 post to this group, send email to everything-list@googlegroups.com. Visit this group at https://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.
Re: Entanglement
From: mailto:agrayson2...@gmail.com>> *Does entanglement -- which occurs whenever two systems interact -- imply non-locality? AG* Not necessarily. If there is a common cause explanation of the correlation, as in classical physics where particles always have definite momenta, then there is no need for a non-local explanation. However, in quantum systems such as the singlet state of entangled spinors, then no common cause or hidden variable explanation is available and we have non-locality. Actually a similar thing happens in any collision between two quantum particles. If we assume an elastic collision, the outgoing particles will be in the form of outgoing spherical waves -- neither the individual momenta or directions are specified by the collision itself. So observing the direction and/or momentum of one particle determines the direction and momentum of the other remote particle. There is no common cause or hidden variable explanation available for this, especially if the observations are at space-like separations. However, as far as I know there are no Bell-like inequalities that are violated by the statistics in this case, so the non-locality is not always obvious. Interestingly, this forms the basis for an important measurement tool at high energy accelerators. Often the output from experiments will be in the form of a missing mass plot, which is constructed by summing the momenta of the observed particles and determining what is missing. This can then be the basis of a search for undetectable or new particles. Bruce -- 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 https://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.
Re: Entanglement
From: mailto:agrayson2...@gmail.com> On Friday, April 20, 2018 at 1:18:32 AM UTC, Bruce wrote: From: *Bruno Marchal* On 18 Apr 2018, at 15:45, Bruce Kellett wrote: From: *Bruno Marchal* On 17 Apr 2018, at 13:52, Bruce Kellett wrote But note particularly that the spin measurement is made in the basis chosen by the experimenter (by orienting his/her magnet). OK. The outcome of the measurement is + or -, For Alice and Bob, OK. not one of the possible infinite set of possible basis vector orientations. The orientation is not measured, it is chose by the experimenter. So that is one potential source of an infinite set of worlds eliminated right away. The singlet is a superposition of two states, + and -: it is not a superposition of possible basis vectors. ? (That is far too ambiguous). ? It is not in the least ambiguous. The singlet state is not a superposition of basis vectors. Actually, to clarify, I meant a superposition of vectors from different bases. ? The singlet state is the superposition of Iup>IMinus> and (Minus>Iup>. Those are not generalized basis vectors: they are eigenfunctions of the spin projection operator in a particular basis. The singlet state is not a superposition of vectors from different bases. *Bruce; I found your above comment confusing and it led to subsequent questions that LC found inappropriately technical or detailed for this forum (which it isn't IMO). Why do you bring in superpositions from different bases? I never saw that used in QM texts.* No, you wouldn't see it in QM texts because it is not something that one would usually do, because, as Brent and I discussed, it is rather pointless. Any vector in the Hilbert space can be expressed as a linear superposition of basis vectors, and the basis vectors in any basis are just further vectors in the space, after all. So expanding in multiple bases can always be reduced to an expansion in a single base. Which base is immaterial. *Additionally, isn't Bruno correct that the above expression for the singlet state which your earlier wrote down, IS a superposition in the UP/DN basis? AG* No, what Bruno wrote was "a superposition of "Iup>IMinus> and (Minus>Iup>", which I took to mean an attempt to expand the singlet state in two bases simultaneuosly -- the (|Plus>, |Minus>) base and the (|up>,|down>) base. It is difficult to see exactly what this would achieve; it seems to be merely a more complicated base. Bruce -- 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 https://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.
Re: Entanglement
On Friday, April 20, 2018 at 4:21:15 AM UTC, agrays...@gmail.com wrote: > > > > On Friday, April 20, 2018 at 2:54:37 AM UTC, Brent wrote: >> >> >> >> On 4/19/2018 7:28 PM, agrays...@gmail.com wrote: >> >> >> >> On Friday, April 20, 2018 at 2:13:20 AM UTC, Brent wrote: >>> >>> >>> >>> On 4/19/2018 6:39 PM, agrays...@gmail.com wrote: >>> >>> >>> >>> On Friday, April 20, 2018 at 12:44:04 AM UTC, Brent wrote: On 4/19/2018 5:29 PM, smitra wrote: > One can a priori rule out any non-local effects using the fact that > the dynamics as described by the Schrödinger equation is local. So, in > any theory where there is no collapse and everything follows from only > the Schrödinger equation, there cannot be non-local effects The wave-function exists in configuration space so a point in it already refers to multiple points in 3space. Brent >>> >>> I've met WF's with variables of space and time. They don't have multiple >>> points in 3 space. Please elaborate as to your meaning. AG >>> >>> >>> The wave function for two particles is a function of six spacial >>> coordinates. >>> >>> Brent >>> >> >> OK, simple, but how is this responsive to smitra's comment? AG >> >> >> So a measurement on one can, assuming some conserved quantity entangling >> them, will have an effect on the other, even if the all the details of >> measurement and decoherence are included and the measurement is treated as >> Everett does. It still zeroes out cross terms in the density matrix that >> correspond ot violation of the conservation law and that entails changing >> the wave function at remote places. >> >> Brent >> > > *Generally speaking, IIUC, any two systems which interact will become > entangled. Does this in principle imply that the property of non locality > exists between them, such as demonstrated by the singlet state, or are > additional assumptions or conditions needed? AG * > *Does entanglement -- which occurs whenever two systems interact -- imply non-locality? AG* -- 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 https://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.
Re: Entanglement
On Friday, April 20, 2018 at 1:18:32 AM UTC, Bruce wrote: > > From: Bruno Marchal > > > On 18 Apr 2018, at 15:45, Bruce Kellett < > bhke...@optusnet.com.au > wrote: > > From: Bruno Marchal > > > On 17 Apr 2018, at 13:52, Bruce Kellett < > bhke...@optusnet.com.au > wrote > > > But note particularly that the spin measurement is made in the basis > chosen by the experimenter (by orienting his/her magnet). > > > OK. > > The outcome of the measurement is + or -, > > > For Alice and Bob, OK. > > not one of the possible infinite set of possible basis vector > orientations. The orientation is not measured, it is chose by the > experimenter. So that is one potential source of an infinite set of worlds > eliminated right away. The singlet is a superposition of two states, + and > -: it is not a superposition of possible basis vectors. > > > ? (That is far too ambiguous). > > > ? It is not in the least ambiguous. The singlet state is not a > superposition of basis vectors. > > > ? > > The singlet state is the superposition of Iup>IMinus> and (Minus>Iup>. > > > Those are not generalized basis vectors: they are eigenfunctions of the > spin projection operator in a particular basis. The singlet state is not a > superposition of vectors from different bases. > *Bruce; I found your above comment confusing and it led to subsequent questions that LC found inappropriately technical or detailed for this forum (which it isn't IMO). Why do you bring in superpositions from different bases? I never saw that used in QM texts. Additionally, isn't Bruno correct that the above expression for the singlet state which your earlier wrote down, IS a superposition in the UP/DN basis? AG * If you think about it for a little, the formalism of QM does not allow the state to be written in any way that could suggest that. I don't know what Everett says in his long text, but if it is any different from the above, then it is not standard quantum mechanics. Deutsch is a different case. He has a very strange notion about what constitutes different worlds in QM. Standard QM and Everett's interpretation are very clear: different worlds arise by the process of decoherence which diagonalizes the density matrix. The net effect is that worlds are, by definition, non interacting (contra Deutsch's ideas). ? This relates to your lack of comprehension above. Patronising !!! Merely pointing out your apparent lack of comprehension when you fail to appreciate the difference between the eigenvectors of a particular operator and the free choice of a basis for Hilbert space. Deutsch has two distinct notions of "world" in his approach. He has the standard Everettian notion of a "relative state" corresponding to each term in the superposition of possible measurement outcomes. These relative states are made definite by decoherence, Relatively. Decoherence is only entanglement (with NON-collapse). So what? and then correspond to different, effectively orthogonal, worlds, each of which represents the experimenter observing one particular result. But Deutsch also has the idea that the infinity of possible bases for an unpolarized qubit also represents an infinity of worlds. That is necessary, and Everett explains this well when he shows that the choice of the base to describe the universal wave is irrelevant. Sure, the choice of basis is irrelevant. It is just that some bases are more useful than others. And there is no use at all in trying to use all bases at once! (A bit like the choice of the universal Turing formalism is irrelevant to get the theology and the physics). This is quite a different notion, and does not occur in Everettian theory. I disagree with this. Well, you are wrong. In this second notion of "world", the worlds remain in superposition and continue to interfere -- there is no separation into disjoint, non-interacting worlds. In fact, it is precisely this continued interference of these supposed "worlds" that is the explanation for the action of quantum computers -- which Deutsch seems to think actually *prove* his notion of quantum "many-worlds". He is out on a limb on this one, and few experts, even in the quantum computing field, agree with Deutsch on this new notion of "worlds". The essential continued interference between the different basis states in fact means that the "worlds" remain inextricable "one world". (See some of Scott Aaronson's comments on Deutsch and many-worlds in his lecture notes on quantum computing.) So when you continue to refer to an "infinity of worlds" for the measurements on the entangled spin states, you are using a notion of "world" that does not occur in Everett, and is inherently controversial, if not entirely meaningless. I use the “Herbrand” interpretation of quantum mechanics without collapse. I mean: it is literal QM (in a sense that logicians have made precise) without collapse up to a choice of any arbitrary base.
Re: Entanglement
On Thursday, April 19, 2018 at 11:26:55 PM UTC-5, Brent wrote: > > > > On 4/19/2018 9:10 PM, agrays...@gmail.com wrote: > > *Can you have superpositions of vectors from different bases? I don't > think so. AG * > > > Sure you can. It just makes the math complicated. > > Brent > The evolution of a quantum state is unitary, and the basis one expands a state can be transformed by unitary operations. The Schroedinger equation can be thought of as a differential equation with solutions that are time dependent transformations of the basis of a state vector. My sense in looking at these comments and the corrections Bruce and Brent write indicate some levels of confusion. If one is asking questions such as AGs above they need to take some time to read carefully a text on quantum mechanics, try to work some problems the text might offer up and think hard on this. A forum like this simply can't provide that, and for myself I do not have time to write 1000 word essays every day on this. None of this comes really easily and to really understand these things it will take some investment of time and effort. 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 post to this group, send email to everything-list@googlegroups.com. Visit this group at https://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.
