Entanglement Theory Query

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Re: Entanglement Theory Query

Postby hyksos on September 12th, 2018, 4:14 pm 

davidm » September 11th, 2018, 12:52 am wrote:Doesn't MWI do away with all this? No spooky action at a distance, no antirealism, no indeterminism, no wave function collapse, no alleged special role for consciousness?

Correct. Yes. And correct.
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Re: Entanglement Theory Query

Postby hyksos on September 12th, 2018, 4:25 pm 

mitchellmckain » September 11th, 2018, 2:49 am wrote:
davidm » September 10th, 2018, 3:52 pm wrote:Doesn't MWI do away with all this? No spooky action at a distance, no antirealism, no indeterminism, no wave function collapse, no alleged special role for consciousness?


Not really. It just changes where the non-locality comes in to how the ele


It does all those things. I think he got it right.

( But just to temper the conversation a tad ), "Consciousness causes collapse" is not really a scientific interpretation within academic physics. It is sort of a popular pseudo-scientific idea -- on par with centrifugal force.
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Re: Entanglement Theory Query

Postby Braininvat on September 12th, 2018, 4:42 pm 

Well, some physicists have gone for the "Wigner's Friend" silliness, where consciousness confers a special causal status over inanimate measuring devices. But it does seem to have been relegated to the pseudoscience bin. I like the way Bayesians shoot it down.

To Mermin among others, the Wigner's friend situation does not lead to a paradox, because there is never a uniquely correct wavefunction for any system. Instead, a wavefunction is a statement of personalist Bayesian probabilities, and moreover, the probabilities that wavefunctions encode are probabilities for experiences that are also personal to the agent who experiences them. As von Baeyer puts it, "Wavefunctions are not tethered to electrons and carried along like haloes hovering over the heads of saints—they are assigned by an agent and depend on the total information available to the agent." Consequently, there is nothing wrong in principle with Wigner and his friend assigning different wavefunctions to the same system.
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Re: Entanglement Theory Query

Postby Braininvat on September 12th, 2018, 5:17 pm 

There's also a lot of merit to decoherent interpretations of many-worlds that use "einselection" to explain how a small number of classical pointer states can emerge from the enormous Hilbert space of superpositions. These provide a better fit with our phenomenal world. This guy...

https://en.m.wikipedia.org/wiki/Wojciech_H._Zurek

....has led the way on this sort of "quantum Darwinism."
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Re: Entanglement Theory Query

Postby Event Horizon on September 12th, 2018, 6:29 pm 

I find some of the arguments hard to follow, I'm no specialist. I'm an ideas guy. I think stuff that I don't even know how I know it. Hence the OP. I'm not sure that we know because its not something most folks would ask. Thanks for so many responses. You take a couple of days off and..woah!
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Re: Entanglement Theory Query

Postby hyksos on September 12th, 2018, 10:43 pm 

As von Baeyer puts it, "Wavefunctions are not tethered to electrons and carried along like haloes hovering over the heads of saints—they are assigned by an agent and depend on the total information available to the agent."

von Baeyer is wrong. Resolution comes from realizing that in the case of the double-slit, the slit itself is comprised of the wave function. There is no "solid material matter" as a distinct entity from Ψ. All is Ψ. This explains why photons refract through transparent glass which is not absorbing the photon. Ψ is different inside the glass than it is in air. The photon is Ψ. There is no translation from or translation to.

It is not the case that solid glass atoms "transmit" their state to Ψ, and then Ψ "suggests" a probability to the refracting photon -- such thinking is a dream either useful for pedagogy, or if not in that context : a desperate attempt to impose mechanico-material paradigms onto quantum mechanics.

Double slits and electron barrier tunneling and other "oddities" are not about photons. Every particle known to science engages in entanglement and interference patterns. All particles down to gluons react probabilistically. There is no "Floor" upon which lower investigations yields classical solidity. Everything is a wave.

This type of thinking was already in the hearts and minds of people developing the Standard Model in the 1960s. Straight chalkboard calculations of the particle spectrum predict (clear as day) that all particles should be massless, and they should be zipping around at c.

They don't -- but why not? Two possible answers... two avenues, (if you will).
Avenue 1) Quantum mechanics is wrong.
Avenue 2) QM is correct. and electro-weak symmetry breaking. "Higg's mechanisms". scalar fields. is why particles have mass.

As we can see from recent experiments at CERN, Avenue 1 ain't looking good right now.

If von Baeyer is suggesting that a person can take a large bag of common sense and classical notions, then stack them up in a pile high enough, you can walk your way up to quantum mechanics. There exists no such pile. Old concepts cannot be re-arranged in a tidy way to make a happy QM picture. QM is not "like" anything from classical mechanics. Consider a more buddhist approach : only with dispensing with your pile of classical physics, gears, solid materiality, and common sense -- can you begin to perceive quantum nature.
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Re: Piling it on

Postby Faradave on September 13th, 2018, 1:39 am 

hyksos wrote:Avenue 1) Quantum mechanics is wrong. Avenue 2) QM is correct.

There's a lot I agree with in your post but some weakness.
For example, you offer a binary choice above, when a qubit would seem more appropriate.
QM is at least incomplete without gravity (Higgs lends itself to inertial mass) but I would not discard it. Nor would I discard the possibility of rearranging concepts of classical physics which is similarly incomplete.

Unfortunately, I must be away for a few days but I'm sure you don't need to another rendition of Phyxed. Episodes of Quantum Spin and Gravity are available to anyone I overlooked.
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Re: Getting Physical

Postby bangstrom on September 13th, 2018, 6:15 am 

Faradave » September 12th, 2018, 2:17 pm wrote:
The shared state is considered "one" and can be modeled in 4D but the particles have separate spatial locations.

This appears to be the point where our views part company. Entangled particles have a shared location which does not become separate until after one of the particles is observed. The particle locations become random with entanglement and are not necessarily the same after entanglement as they were before.

Faradave » September 12th, 2018, 2:17 pm wrote:
Information has no existence apart form the physical. It is always expressed in terms of mass-energy thus, restricted by universal speed limit c.


This is true of classical information but quantum information is the thing that “informs” a particle of its quantum identity. It informs an electron as to how to be an electron or a proton how to be a proton as well as giving particles their independent properties of such things as spin direction or polarity. Quantum information maintains particle identities across distances beyond those traversable by classical communication limited to c. In quantum physics distant interactions can be instantaneous.

Faradave » September 12th, 2018, 2:17 pm wrote:
It's fine to consider an entanglement to represent one state of information and disentanglement to be another form. But change in state is not the same as communication, even if it appears to have been coordinated.

In a similar sense, the universe imposes physical laws throughout space and time (that's what makes them laws) but that universal coordination of observed laws in no way requires the coordinated objects to communicate with each other faster than c.


Entanglement is a superposition of particle identities with two remote particles sharing the same identity as if two halves of a single particle having a common Schroedinger wavefunction. Entanglement is also a superposition of location. The location of entangled particles is said to be “indeterminate.” We can’t say particle A is in location A or particle B is in location B until after one of the particles is observed which instantly fixes the location of both particles. The locations of the particles after entanglement is random and not necessarily the same as it was before entanglement.

If the locations of the particles after entanglement is not the same as it was before, it appears to us that the particles have instantly swapped locations with neither particle having traveled through the space between. The particles have not physically swapped locations but they have swapped identities. Quantum information has randomly swapped their individual identities.
We know the Eiffel Tower is in Paris and Leaning Tower is in Pizza and the two never swap locations but this is not necessarily true at the particle level.

The loss of entanglement (decoherence) is instant (non-local) or at least far faster than c. If we have an entangled electron in a high energy orbit entangled with a low energy electron in a distant atom and the post-entanglement condition later finds the low energy electron with a higher energy than before, we know the other atom now has an electron at a lower energy. The energy levels may be differently assigned but the total energy is conserved.

Energy has randomly swapped locations after entanglement, but not by passing through the space between so the speed of the coordination is instant and not limited by c. The only change is for one electron to jump to a higher level orbit at the same instant the other electron drops to a lower energy orbit.

Energy has vanished from one location and instantly appeared at another without passing through the space between but we can never see the change as instant because, as we know from SR, two simultaneous events separated by space will always be observed as separated by time at the rate of one second for every 300,000 km of distance. This implies that c is a dimensional constant and not the speed of energy as it travels through space. There is no "traveling through space" so there is no speed for energy.
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Re: Entanglement Theory Query

Postby bangstrom on September 13th, 2018, 6:40 am 

JustAsking » September 12th, 2018, 12:45 pm wrote: There aren't two particles, there's only one, in a higher dimension. Of course we only observe the particles in 3D, and so posit exchanges of info and whatnot. Well there is no exchange of info or any actual entanglement I suppose since it's just the same single 4D particle appearing to us to be in two different 3D places.

Thoughts?

Whether your idea is correct or not, that is essentially how it works.
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Re: Getting Physical

Postby mitchellmckain on September 13th, 2018, 10:32 am 

bangstrom » September 13th, 2018, 5:15 am wrote:Entanglement is also a superposition of location. The location of entangled particles is said to be “indeterminate.” We can’t say particle A is in location A or particle B is in location B until after one of the particles is observed which instantly fixes the location of both particles. The locations of the particles after entanglement is random and not necessarily the same as it was before entanglement.

No, this is not what entanglement is. And whether you can have this sort of entanglement is not something you have demonstrated. Just because you can have a superposition of states doesn't mean that kind of superposition can be entangled. Are you just making things up?
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Re: Model Muddle

Postby Faradave on September 13th, 2018, 10:43 am 

bangstrom wrote:This appears to be the point where our views part company.

Interesting post! I'm literally heading out the door for a few days, so not intentionally neglecting you. There's enough there for me to surmise that we are each relying on different examples of entanglement. The two most commonly used are the polarities of two photons and the quantum spins of two electrons.

Above, I noted my use of the latter, where there are two different electrons whose spins have become entangled in a total-spin-zero or total-spin-one shared state. I know of no theory which claims these are the same particle, however conventional field theory would describe each as an excitation of a common "electron field". I depart from that view, considering each fermion to be associated with an individual "native" field.

bangstrom wrote:information is the thing that “informs” a particle of its quantum identity. It informs an electron as to how to be an electron

I don't see how this escapes the obligatory association of information with mass-energy (i.e. "the physical"). It was Rolf Landauer who said "Information is physical." That is, there no such thing as information by itself, apart from a physical manifestation. It would be devilishly hard to even describe, like the quantity 14. Though we take "real" numbers for granted, without some unit to point to they are meaninglessly abstract.
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Re: Entanglement Theory Query

Postby Braininvat on September 13th, 2018, 12:02 pm 

Yeah, I'll always find language like "informs an electron how to be an electron," or "everything is phi" to be rather supernatural for my taste. The "laws" of nature that we have created are descriptive, not prescriptive Platonic fields. Wavefunctions are not like haloes hovering over the heads of saints.
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Re: Getting Physical

Postby JustAsking on September 13th, 2018, 1:03 pm 

Faradave » September 12th, 2018, 2:17 pm wrote:
bangstrom wrote:I can agree with all that except for the exclusion of a communication of information.

dandelion wrote:I prefer views agreeing with exchange of information

Information has no existence apart form the physical. It is always expressed in terms of mass-energy thus, restricted by universal speed limit c.

It's fine to consider an entanglement to represent one state of information and disentanglement to be another form. But change in state is not the same as communication, even if it appears to have been coordinated.

In a similar sense, the universe imposes the same physical laws throughout space and time (that's what makes them laws) but that universal coordination of observed laws in no way requires the coordinated objects to communicate with each other faster than c.

JustAsking wrote:Could the same basic idea apply with entangled particles? There aren't two particles, there's only one, in a higher dimension.

Hi JA,
The shared state is considered "one" and can be modeled in 4D but the particles have separate spatial locations. One of the pair can annihilate or drop into a blackhole without the other (of course breaking the entanglement), so in most respects they meet the same typical properties of individual particles.
That's the shared state being modeled in 4D which is a mathematical operation. I mean there's a single physical particle that only appears spatially separated in 3D but isn't in 4D.
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Re: Getting Physical

Postby bangstrom on September 13th, 2018, 1:51 pm 

mitchellmckain » September 13th, 2018, 9:32 am wrote:
bangstrom » September 13th, 2018, 5:15 am wrote:Entanglement is also a superposition of location. The location of entangled particles is said to be “indeterminate.” We can’t say particle A is in location A or particle B is in location B until after one of the particles is observed which instantly fixes the location of both particles. The locations of the particles after entanglement is random and not necessarily the same as it was before entanglement.

No, this is not what entanglement is. And whether you can have this sort of entanglement is not something you have demonstrated. Just because you can have a superposition of states doesn't mean that kind of superposition can be entangled. Are you just making things up?


Entanglement is the momentary and non-local superposition of quantum states. How is that wrong?

The theory of what we now call “entanglement” as being the mechanism behind the non-local transmission of EM energy has been around since proposed by Hugo Tetrode in 1922 and Einstein pointed out to Wheeler and Feynman that their “absorber” theory bore a close resemblance to Tetrode’s except for their many magic photons that went everywhere and did everything and then disappeared.

The most recent formulation of Tetrode’s theory is John Cramer’s Transactional Interpretation of Quantum Mechanics “TIQM” which is essentially the older W-F Absorber theory without the photon particles traveling through space.

A part of the theory is that the identity of a particle can be shared with another particle and the particles can later randomly swap identities making it appear that they have swapped locations without traveling through the space between. This possibility is demonstrated in any experiment involving quantum teleportation.
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Re: Getting Physical

Postby mitchellmckain on September 13th, 2018, 5:56 pm 

bangstrom » September 13th, 2018, 12:51 pm wrote:Entanglement is the momentary and non-local superposition of quantum states. How is that wrong?

Entanglement is when TWO or more particles are in a state which must be described by the same wave function because it is in a superposition with respect to the eigenestates of some measurement operator so that the measurements of the two particles must be correlated with each other.

It doesn't have to be nonlocal and just because a superposition is non-local doesn't make it entanglement. If it is just a single particle then there is no entanglement. Also if the wave functions of the two or more particles are separable so all measurements of one particle are independent of the measurements of the other particle then it is not entanglement.

bangstrom » September 13th, 2018, 12:51 pm wrote:The theory of what we now call “entanglement” as being the mechanism behind the non-local transmission of EM energy has been around since proposed by Hugo Tetrode in 1922 and Einstein pointed out to Wheeler and Feynman that their “absorber” theory bore a close resemblance to Tetrode’s except for their many magic photons that went everywhere and did everything and then disappeared.

Entanglement cannot be used for the non-local transmission of energy (i.e. for the super-luminal transmission of energy over a space-like interval). This is wrong.

It is true that such an hypothesis was suggested by Masohira Hota, but it has been proven to be incorrect and that such a thing cannot happen. Even if you entangle particles in a superposition of different energy states (and I have seen no evidence that such a things is possible), this would only cause them to take energy from their surroundings. No energy can be transmitted in this way.

It is possible to transmit energy by entanglement over a time-like distance however. But this is not a case in which you would use the term "non-local."

As for ideas of Hugo Tetrode, I will say that is comparable with the idea of phlogiston proposed by J. J. Becher. Surely you know the difference between a scientific hypothesis and a scientific fact.

bangstrom » September 13th, 2018, 12:51 pm wrote:The most recent formulation of Tetrode’s theory is John Cramer’s Transactional Interpretation of Quantum Mechanics “TIQM” which is essentially the older W-F Absorber theory without the photon particles traveling through space.

John Cramer explored the possibility of non-local quantum communication and found that it would not work.

bangstrom » September 13th, 2018, 12:51 pm wrote:A part of the theory is that the identity of a particle can be shared with another particle and the particles can later randomly swap identities making it appear that they have swapped locations without traveling through the space between. This possibility is demonstrated in any experiment involving quantum teleportation.

This is nonsense. Identical particles have no individual identity. This fact is a crucial part of the laws of physics. There is is no swapping any particles there is only the decoherence of a superpostion.
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Re: Piling it on

Postby hyksos on September 13th, 2018, 11:41 pm 

Faradave » September 13th, 2018, 9:39 am wrote:
hyksos wrote:Avenue 1) Quantum mechanics is wrong. Avenue 2) QM is correct.

There's a lot I agree with in your post but some weakness.
For example, you offer a binary choice above, when a qubit would seem more appropriate.
QM is at least incomplete without gravity (Higgs lends itself to inertial mass) but I would not discard it. Nor would I discard the possibility of rearranging concepts of classical physics which is similarly incomplete.

Unfortunately, I must be away for a few days but I'm sure you don't need to another rendition of Phyxed. Episodes of Quantum Spin and Gravity are available to anyone I overlooked.

Now I am reading all your posts in a completely different voice than before.
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Re: Getting Physical

Postby bangstrom on September 14th, 2018, 2:09 am 

mitchellmckain » September 13th, 2018, 4:56 pm wrote:
Entanglement is when TWO or more particles are in a state which must be described by the same wave function because it is in a superposition with respect to the eigenestates of some measurement operator so that the measurements of the two particles must be correlated with each other.

That sounds more like my understanding of entanglement than your previous comments on the subject or even those of your most recent post.

mitchellmckain » September 13th, 2018, 4:56 pm wrote:
Entanglement cannot be used for the non-local transmission of energy (i.e. for the super-luminal transmission of energy over a space-like interval). This is wrong.


If by some wild discontinuity in the spacetime continuum, the superluminal and non-local transmission of energy happens. How could we identify it as being any different from the classical transmission of a radio signal.
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Re: Getting Physical

Postby mitchellmckain on September 14th, 2018, 4:47 am 

bangstrom » September 14th, 2018, 1:09 am wrote:That sounds more like my understanding of entanglement than your previous comments on the subject or even those of your most recent post.

But the important thing is that this does not agree with what you just said. Precision in science is crucial for that is one of the important differences from philosophy and theology.

bangstrom » September 14th, 2018, 1:09 am wrote:If by some wild discontinuity in the spacetime continuum, the superluminal and non-local transmission of energy happens. How could we identify it as being any different from the classical transmission of a radio signal.

Then the universe would be incoherent with no order between cause and effect. And we would have good cause to think the universe is nothing but crazy dream without any consistent rules. This is because what you suggest is precluded by the space-time structure of the universe itself which separates past from future. You would only think it is possible if you are imposing an Euclidean structure on it, which may be good for movie films but not for the universe we live in.
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Re: Entanglement Theory Query

Postby dandelion on September 15th, 2018, 3:58 am 

I’m sorry, Faradave, I think I misunderstood the explanation of secret made public. Public had me thinking of lots of different measurements giving me an impression that it was as if you were saying there wouldn’t be change in many measurements which I think now was wrong of me to think you’d suggested anything like that from what you wrote, sorry. On the other discussion, it is more philosophically unsuited here and questionable, but just generally maybe notions of physical waves can tend to suggest all following causal flows or something like that, which might lend more to sorts of retrocausal language, and different added methods or cancelling out may offer suggestions more towards statistics, like I think Bangstrom mentioned at some stage here.
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Re: Getting Physical

Postby bangstrom on September 15th, 2018, 5:41 am 

mitchellmckain » September 14th, 2018, 3:47 am wrote:
bangstrom » September 14th, 2018, 1:09 am wrote:That sounds more like my understanding of entanglement than your previous comments on the subject or even those of your most recent post.

But the important thing is that this does not agree with what you just said. Precision in science is crucial for that is one of the important differences from philosophy and theology.

How is this different from what I said? Here are three of my complaints about your comments.

You said,"It doesn't have to be nonlocal and just because a superposition is non-local doesn't make it entanglement."

Entanglement is a non-local superposition of quantum states. Every time.

You said,"You said, “Identical particles have no individual identity.”

Of course not. That is why they are called “identical” and we don’t need a law of physics for that. Quantum superposition requires that entangled particles have opposite quantum identities.

If an electron in a spin-up position spontaneously entangles with an electron in a spin-down position and later decoherence leaves the spin-up electron where the spin-down electron was previously and vice versa, then we have two particles that have swapped identities. Our observation is that the two electrons have swapped locations but neither electron needs to have moved from its original position. They swapped identities- not locations.

You said, "Yes, superpositions can be non-local but its decoherence involves no transmission of information, because there is no information content in random results."

The loss of entanglement may be random or cause unknown but the opposite identities of the particles that drop out indicates a common coordination between particles indicating that some form of non-random communication has been sent and received .

Quantum information is defined as the mysterious thing that informs particles of their quantum identities. You may not approve of the statement that “information” has been exchanged when entanglement is lost but the event is customarily described as an exchange of “quantum information” and quantum information is not exactly the same thing as classical information.

mitchellmckain » September 14th, 2018, 3:47 am wrote:
bangstrom » September 14th, 2018, 1:09 am wrote:If by some wild discontinuity in the spacetime continuum, the superluminal and non-local transmission of energy happens. How could we identify it as being any different from the classical transmission of a radio signal.

Then the universe would be incoherent with no order between cause and effect. And we would have good cause to think the universe is nothing but crazy dream without any consistent rules. This is because what you suggest is precluded by the space-time structure of the universe itself which separates past from future. You would only think it is possible if you are imposing an Euclidean structure on it, which may be good for movie films but not for the universe we live in.


The observation of quantum entanglement demonstrates that non-local interaction among remote particles is possible and it can happen without the total destruction of the universe. Entanglement side steps the usual space time structure that separates past from future but it is likely that only small minority of particles are entangled at any one time so the timing of direct physical interactions among particles that we frequently observe as cause and effect is limited by the permeability and permittivity of space. These two properties of spacetime are responsible for the constant ratio of c for the space/time separation between cause and effect. That is why these two properties are referred to as the “speed of causality.”
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Re: Getting Physical

Postby mitchellmckain on September 16th, 2018, 3:47 pm 

bangstrom » September 15th, 2018, 4:41 am wrote:
mitchellmckain » September 14th, 2018, 3:47 am wrote:But the important thing is that this does not agree with what you just said. Precision in science is crucial for that is one of the important differences from philosophy and theology.

How is this different from what I said? Here are three of my complaints about your comments.

You said,"It doesn't have to be nonlocal and just because a superposition is non-local doesn't make it entanglement."

Entanglement is a non-local superposition of quantum states. Every time.

Incorrect. It CAN be non-local but no it doesn't have to be. Non-locality is not what makes it entanglement. What makes it entanglement is that TWO or more particles are in a state which must be described by the same wave function because it is in a superposition with respect to the eigenestates of some measurement operator so that the measurements of the two particles must be correlated with each other.

Just because non-locality is what make you think entanglement is useful to the rhetoric you are pushing doesn't mean this has anything to do with what defines entanglement.

bangstrom » September 15th, 2018, 4:41 am wrote:You said,"You said, “Identical particles have no individual identity.”

Of course not. That is why they are called “identical” and we don’t need a law of physics for that. Quantum superposition requires that entangled particles have opposite quantum identities.

Incorrect you are editing my words. What I said was...

bangstrom » September 15th, 2018, 4:41 am wrote:Quantum superposition requires that entangled particles have opposite quantum identities.

Why are you talking about quantum identities when they don't have any such thing. There is only the type of particle and the quantum state. And they certainly don't necessarily have opposite states. You can set an entanglement where they have the same quantum state. Do you want me to write down such a wave function?

bangstrom » September 15th, 2018, 4:41 am wrote:If an electron in a spin-up position spontaneously entangles with an electron in a spin-down position and later decoherence leaves the spin-up electron where the spin-down electron was previously and vice versa, then we have two particles that have swapped identities. Our observation is that the two electrons have swapped locations but neither electron needs to have moved from its original position. They swapped identities- not locations.

Spontaneously entangles? This makes me think you have no idea what you are talking about. A pair of particles are usually entangled because they are produced under conditions where some quantity like angular momentum must be conserved. And again you speak of identities when there is no such thing.

bangstrom » September 15th, 2018, 4:41 am wrote:You said, "Yes, superpositions can be non-local but its decoherence involves no transmission of information, because there is no information content in random results."

The loss of entanglement may be random or cause unknown but the opposite identities of the particles that drop out indicates a common coordination between particles indicating that some form of non-random communication has been sent and received .

No it does not. The most it indicates is the non-locality of the quantum state. There is NO communication, there is only the correlation of random data. And in information theory random data equals no information content.

bangstrom » September 15th, 2018, 4:41 am wrote:Quantum information is defined as the mysterious thing that informs particles of their quantum identities. You may not approve of the statement that “information” has been exchanged when entanglement is lost but the event is customarily described as an exchange of “quantum information” and quantum information is not exactly the same thing as classical information.

NO. It is not defined as any such thing.

From wikipedia:
In physics and computer science, quantum information is information that is held in the state of a quantum system.

There is no transmission of such information, because both have this information already. There is only the non-local change of state by decoherence to a random part of the superposition.

bangstrom » September 15th, 2018, 4:41 am wrote:
mitchellmckain » September 14th, 2018, 3:47 am wrote:Then the universe would be incoherent with no order between cause and effect. And we would have good cause to think the universe is nothing but crazy dream without any consistent rules. This is because what you suggest is precluded by the space-time structure of the universe itself which separates past from future. You would only think it is possible if you are imposing an Euclidean structure on it, which may be good for movie films but not for the universe we live in.

The observation of quantum entanglement demonstrates that non-local interaction among remote particles is possible and it can happen without the total destruction of the universe. Entanglement side steps the usual space time structure that separates past from future but it is likely that only small minority of particles are entangled at any one time so the timing of direct physical interactions among particles that we frequently observe as cause and effect is limited by the permeability and permittivity of space. These two properties of spacetime are responsible for the constant ratio of c for the space/time separation between cause and effect. That is why these two properties are referred to as the “speed of causality.”

Incorrect. There is no interaction. Decoherence is not an interaction. You cannot side step the structure of the universe, you can only obstinately ignore it in order to insist on nonsensical ideas. All great for sci-fi and fantasy stories but having nothing to do with the reality of the universe in which we live.
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Re: Getting Physical

Postby bangstrom on September 17th, 2018, 5:21 am 

mitchellmckain » September 16th, 2018, 2:47 pm wrote:
Incorrect. It CAN be non-local but no it doesn't have to be. Non-locality is not what makes it entanglement. What makes it entanglement is that TWO or more particles are in a state which must be described by the same wave function because it is in a superposition with respect to the eigenestates of some measurement operator so that the measurements of the two particles must be correlated with each other.


Entanglement is always non-local otherwise it would would be an ordinary classical interaction. Entanglement has aspects of an instant “spooky action at a distance” which distinguishes it from the classical interactions.

mitchellmckain » September 16th, 2018, 2:47 pm wrote:
Incorrect you are editing my words. What I said was...

bangstrom » September 15th, 2018, 4:41 am wrote:Quantum superposition requires that entangled particles have opposite quantum identities.


How can you that be what you said when the quote has my name on it? Or did you forget to mention what it was you said?

mitchellmckain » September 16th, 2018, 2:47 pm wrote:
Why are you talking about quantum identities when they don't have any such thing. There is only the type of particle and the quantum state. And they certainly don't necessarily have opposite states. You can set an entanglement where they have the same quantum state. Do you want me to write down such a wave function?

If you have two entangled particles, both having the same quantum state rather than opposite states, how would you ever know they were entangled?

mitchellmckain » September 16th, 2018, 2:47 pm wrote:
Spontaneously entangles? This makes me think you have no idea what you are talking about. A pair of particles are usually entangled because they are produced under conditions where some quantity like angular momentum must be conserved. And again you speak of identities when there is no such thing.


The local generation of entangled particles is necessary for experimental purposes to verify that the particles are entangled but Nature does not have the same limitations. Spontaneous entanglement is extremely difficult to observe over a distance but quantum tunneling and field effect transistors are two micro examples.

mitchellmckain » September 16th, 2018, 2:47 pm wrote:
bangstrom » September 15th, 2018, 4:41 am wrote:Quantum information is defined as the mysterious thing that informs particles of their quantum identities. You may not approve of the statement that “information” has been exchanged when entanglement is lost but the event is customarily described as an exchange of “quantum information” and quantum information is not exactly the same thing as classical information.

NO. It is not defined as any such thing.

From wikipedia:
In physics and computer science, quantum information is information that is held in the state of a quantum system.

There is no transmission of such information, because both have this information already. There is only the non-local change of state by decoherence to a random part of the superposition.


There is no transmission of “classical” information but the correlation involves “quantum” information "informing" the particles that they no longer have a shared identity. "Quantum" information is what it is called whether you approve or not and quantum information differs strongly from classical information. They are not the same thing.

mitchellmckain » September 16th, 2018, 2:47 pm wrote:Incorrect. There is no interaction. Decoherence is not an interaction. You cannot side step the structure of the universe, you can only obstinately ignore it in order to insist on nonsensical ideas. All great for sci-fi and fantasy stories but having nothing to do with the reality of the universe in which we live.

It is called an interaction whether you consider it to be or not.

Quhttp://www.quantuminteraction.org/
“Quantum Interaction is an emerging discipline in artificial intelligence combining mathematics, physics, cognitive and computer sciences."
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Re: Entanglement Theory Query

Postby Event Horizon on September 17th, 2018, 3:38 pm 

Guys, I literally just came across this: https://www.livescience.com/63595-schro ... tification

I haven't read it through yet, but clearly it's a fascinating development. A quantum particle can apparently be at two simultaneous temperatures. Moreover, what does it mean to our concept of QM as is? It kinda begs the question, just how many other things can hold simultaneously binary states?
Or rather, perhaps, how many binary states can exist?

I assume the article is reliable, unlike my braincell. (singular!).
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Re: Entanglement Theory Query

Postby hyksos on September 17th, 2018, 9:53 pm 

Event Horizon » September 17th, 2018, 11:38 pm wrote:Guys, I literally just came across this: https://www.livescience.com/63595-schro ... tification

I haven't read it through yet, but clearly it's a fascinating development. A quantum particle can apparently be at two simultaneous temperatures. Moreover, what does it mean to our concept of QM as is? It kinda begs the question, just how many other things can hold simultaneously binary states?
Or rather, perhaps, how many binary states can exist?

I assume the article is reliable, unlike my braincell. (singular!).

Thanks for this link.

From your link, I drilled down a little bit, and I found some eye-opening material.
When Landauer argued in 1961 that any physical realisation of erasure of information has a fundamental thermodynamic work cost he irrevocably linked thermodynamics and information theory1,2,3,4,5,6,7,8,9. A practical consequence of this insight is that all computers must dissipate a minimal amount of heat in each irreversible computing step, a threshold that is becoming a concern with future computer chips entering atomic scales. The treatment of general quantum information processing tasks within the wider framework of quantum thermodynamics has only recently begun.

taken from https://www.nature.com/articles/srep22174

The lab that performed the research about temperature being uncertain is here http://www.quantum-exeter.co.uk/research/
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Re: Entanglement Theory Query

Postby Event Horizon on September 20th, 2018, 6:48 pm 

Apparently, I hear, the destruction of information has been found to have a thermal component. I found this paper on just this very thing. https://www.nature.com/articles/s41534-018-0069-z

I don't understand the math etc, so you guys may get more from it than me. Still, its pertinent as it kinda qualifies information as a thing. I don't know what manner of thing exactly. Sorry, I think I'm getting a bit rabbit-hole syndromey.
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