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bangstrom

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  1. Charged particles, especially electrons, can spontaneously entangle with any other similar charged particle on the same light cone so entanglement need not begin as local. The initiation of entanglement, in this case, is instant as is the loss of entanglement and decoherence can span any distance which makes it a non-local action at a distance. Two independent particles need not be anti-coordinated before entanglement, but upon entanglement, their individual quantum properties become indeterminate (superimposed). Later when the first particle is observed, the same quantum property for both is found to be anti-coordinated. It is logical to say that their properties became anti-coordinated and have remained so from the start but this is one of the several ‘hidden variables’ that was eliminated as invalid by experiments involving the violation of Bell’s inequalities. Independent of this, Anton Zeilinger, with his quantum teleportation, has demonstrated that an entire cascade of quantum properties can be instantly reversed to conform to a later entanglement no matter what the unobserved outcome of the first entanglement may have been. If 0’s and 1’s are considered as the observations, their values can be instantly reversed to 1’s and 0’s indicating that the observed outcome of an experiment need not be fixed from the start but still they are anti-coordinated at the end. It could be that the first observation ends the entanglement and begins the anti-coordination. This suggests some kind of signal from the first observation to the second indicating a signal sent and a signal received. If you exclude entanglement as an example of non-locality, what could be considered as non-local?
  2. Evolution is a long term series of local events. It is not entanglement.
  3. Yes, as I explained, outside observations, whether the observers are in motion or not, do not affect the results of the experiment which is why our circular discussion about SR and outside observations were irrelevant. That was my suggestion to get off the topic. Perhaps I should have written it in red with a large font. With entanglement, the observation of one quantum property at one point instantly tells us something we can find expect to find about its entangled partner(s) at another point. We can expect to find that the same observed property will be anti-coordinated with the first observation. That appears to be contrary to local realism and the EPR effect. In this case, the observation of the second particle depends on an observation at another point possibly a great distance away. How is that not non-locality? Nothing has been shown to transpire between the particles. Right, "Nothing has been shown to transpire between the particles." That is why it is called, 'Instant action at a distance.' There is nothing to see between the particles. The correlation is observed at the ends.
  4. Agreed, that was the primary topic. And I still don't understand your explanations, which is why I can’t tell if yours is valid observation or a mathematical obfuscation. What is called "local" in Hermitian space is not what is called "local" outside the Hermitian, and as long as the terms are defined, I see no problem with calling entanglement non-local. I understand how entanglement is a sort of hybrid state where two remote particles act locally as if side-by-side so entanglement has a local component but the instant decoherence of entanglement across, possibly extra galactic distances, is non-local by conventional definitions as is the apparent signal, if there really is a signal. And is the Lagrangian of the wave function of entanglement not a non-local Lagrangian? Not that I am qualified to judge. I will leave that up to you. https://en.wikipedia.org/wiki/Nonlocal_Lagrangian In field theory, a nonlocal Lagrangian is a Lagrangian, a type of functional L [ ϕ ( x ) ] {\displaystyle {\mathcal {L}}[\phi (x)]} containing terms that are nonlocal in the fields ϕ ( x ) {\displaystyle \phi (x)} , i.e. not polynomials or functions of the fields or their derivatives evaluated at a single point in the space of dynamical parameters I disagree but I will let that pass as your opinion. I also agreed that entanglement could not be used as a FTL communication at the macro level. That doesn't mean it is not superluminal at the particle level. I understand how entanglement is a sort of hybrid state where two remote particles act locally as if side-by-side so entanglement is not totally non-local but the instant decoherence of entanglement is non-local by conventional definitions as is the apparent signal, if there really is a signal. I said SR is “meta” to the topic of entanglement and how outside observers, with their varied observations, can not change the temporal order of events in an experiment. In other words, SR is irrelevant to the discussion of experiments involving entanglement. I am not saying SR is not important. It just isn't relevant to understanding most experiments involving entanglement, their collection of data, or calculations of the results. The experiments themselves are normally setup with SR in mind so they eliminate any possible SR related artifacts in the timing of events which is why SR is not found in the calculations or discussions of the results. Are you saying nothing that transpires between the entangled particles has been demonstrated to be FTL? Yes, that is what I said.
  5. Hopefully, yes. I appreciate your efforts and support the accuracy of your description. The majority of the 22 pages were not about entanglement but they veered off into circular discussions of unrelated topics such as fine points of SR sprinkled with many comments of a personal nature so little was accomplished. We should be able to do better. Quantum particles have no identity in the sense of Dirac's observation that a an electron on Earth is no different from other electrons in the cosmos. It is as if there is only one electron that appears to be popping up everywhere at once. But electrons do take on individual properties. The disagreement de jour centers around my reply to your statement, “OK, @bangstrom. Enough is enough. Take a code "0" and "1." Describe a protocol that sends either "0" or "1" to a distant observer by using an entangled state. Describe it clearly.” To which I replied,”This is impossible for the sender. They can’t know what they sent or describe it. A person on the sending end can generate a pair of entangled particles and send one off but they can’t know the identity of which one they sent or which one they retain. If they observe the identity of their own particle, they break the entanglement.” To which you replied, “In other words. You're saying that somehow, what you say is true, just because you say so, but nobody can ascertain experimentally, or even in principle, that it's true.” I don’t find this to be my opinion alone and I try never to make a statement that I can’t support so here is a quote from Wikipedia in support of my claim that, “If they observe the identity of their own particle, they break the entanglement.” https://en.wikipedia.org/wiki/Quantum_entanglement “The paradox is that a measurement made on either of the particles apparently collapses the state of the entire entangled system—and does so instantaneously, before any information about the measurement result could have been communicated to the other particle (assuming that information cannot travel faster than light) and hence assured the "proper" outcome of the measurement of the other part of the entangled pair. In the Copenhagen interpretation, the result of a spin measurement on one of the particles is a collapse into a state in which each particle has a definite spin (either up or down) along the axis of measurement. The outcome is taken to be random, with each possibility having a probability of 50%. However, if both spins are measured along the same axis, they are found to be anti-correlated. This means that the random outcome of the measurement made on one particle seems to have been transmitted to the other, so that it can make the "right choice" when it too is measured.[34]
  6. This is impossible for the sender. They can’t know what they sent or describe it. A person on the sending end can generate a pair of entangled particles and send one off but they can’t know the identity of which one they sent or which one they retain. If they observe the identity of their own particle, they break the entanglement. The receiver instantly knows if it is “0” or “1” but they can’t know what it means because even the sender can't know what they sent. I think you meant SLT, superluminal time. All the timing data for the experiment is automatically recorded in real time at both locations and at the time of decoherence. It may be much later when the data is analyzed and it is found that the information about some property of the second entangled particle arrived before any possibility of a light signal. A later analysis of the data can not go back in time and rewrite recorded history. Some say that does violate SR but I say it only violates Einstein’s second postulate about nothing being faster than light. His second postulate was instrumental in formulating SR but it remains a provisional statement that is no longer supported by experimental evidence. The evidence was not available in Einsteins time but it was much speculated before his time and repeatedly proven true after. I’m just telling it like it is.
  7. That goes back to the old example where lightning strikes both ends a train simultaneously on both ends relative to an observer in the center. An observer at the front will say it struck the front first and an observer at the rear will say it struck the rear first. Those are examples using an energy carrying light signal that observers see differently and SR applies different directional observations to the observation of entanglement as well. An example of a signal carrying information but not energy would be a signal involving entanglement. That is my answer and I have no other. Your question #2 is a koan, 先 生. Like, What is the sound of one hand clapping” An “Information transfer or signal, without any energy or matter involved?“ That would be a signal from nowhere yet to arrive anywhere.
  8. I make no claims to understand all of it. Is this even a question? “You have placed the germ of the answer in your use of 'former partner'. I was waiting for you to explain what you meant. There is no need to know anything about the spin states of a Cooper pair. I explained how it is done with diamonds and there are articles that explain how it is done if you care to look. It is done by illuminating the diamonds with lasers and wait for them to emit a pair of entangled photons. They measure the spin state of the electrons indirectly by observing circular polarization of the photons emitted. They measure the polarizations by an unusual method using lasers that I am not familiar with but I am looking into how it is done. Absolutely not. Where did you get that crazy idea? I know what isn’t entanglement when it is obvious that it isn’t. This is why Ghideon's explanation fails the Bell test by its lack of possible anti-coordinated combinations. If two people get married, they instantly become husband and wife at the pronouncement. But at the same pronouncement, if one is alive, the other drops dead. I have studied the maths of Bell's Inequalities. I am always open to new ideas. I am open to open old ideas if I find them to be sensible and logical. But, old ideas that have been debunked for more than fifty years- not so much. That is things things like the non-existence of non-locality (instant action at a distance) or hidden variables with entanglement.
  9. The twins paradox still includes a time dilation as a part of the explanation. The other part is travel through space and then how to combine the two. Einstein said gravity and acceleration are equivalent. We can ignore gravity for the twin in space but the twin in space has to deal with acceleration. As you probably know, gravity is defined as curved spacetime and acceleration is likewise curved spacetime. It is hard to visualize how either space or time can curve so I prefer to think of gravity as shorter space and slower time. The space traveling twin experiences a greater acceleration than his Earthbound brother so, just as a greater gravitational field slows time, greater acceleration slows time by an equal amount. So the space traveling twin’s clock ticks slower and he ages less than his brother. Acceleration is the physical mechanism that slows time. If the space traveler is traveling to a destination a light year away, averaging 80% the speed of light, he will reach his destination in half the estimated time by his clock because he is either accelerated by speeding up or slowing to a stop. And it will be the same as he returns to Earth. If he measures his travel distance by time, he will say he made the trip to his destination and back in one year instead of the expected two years and he will have aged by one year while gone. His twin will have aged by two years if he was away form Earth’s gravity. But by any observation, if he traveled by train and measured the distance by the number of ties in the track, all observers would say he traveled the same distance in ties crossed. But he covered the distance in half the expected time so he took a shortcut through spacetime. I like to think if the little squares on a Minkowski or Epstein diagram as little time zones. Each square you pass in any direction is essentially a trip to an earlier time zone. Travel through space is simultaneously travel through both space and time as Minkowski said. Each time zone you cross whether coming or going subtracts a little time from your clock.
  10. Please, please don't ask me about electrons in a hydrogen molecule! I am avoiding that question like the corona. You didn't specify what you were asking for in your question, "Can you provide an actual example of the circumstances for these two electrons ?" so I didn't know what what kind of answer you were expecting. Why do you think I don't know there are two electrons in a hydrogen molecule and they are entangled? The electrons in the electron clouds of all the elements are also entangled. In ultra-cold superconducting materials, electrons circulate as entangled pairs called Cooper pairs. They are forced to quantum tunnel out of the superconductor by the application of a high voltage at which time the entangled electrons separate naturally by mutual repulsion as they leave in different directions. https://news.softpedia.com/news/Extracting-Entangled-Electrons-from-Superconductors-124341.shtml "Extracting Entangled Electrons from Superconductor In its experiments, the UB team used an innovative approach to mining the electrons out of the material. It created an aluminum superconductor and attached nanowires to it that could have represented the particles' way out. Ironically, the key to the entire process did not prove to be offering the electron pairs a way out, but actually preventing them from getting out. When a high voltage was applied to the nanowires, they started acting like barriers, and electrons are known to perform something called quantum tunneling when presented with such an obstacle. The pairs essentially drill their way out through the barrier, at a very small pace, allowing the researchers to catch and isolate them as they emerge. As they exit the superconductor and the nanowires, the electrons' natural repulsion force kicks in, and the pair splits. Each nanowire has a junction, and each of the possible avenues can only house one electron. Using this method, the UB team was able to produce and then separate streams of entangled electrons" The Henson experiment in 2015 used a similar method to obtain their entangled electrons. They started with an ultra-cold superconducting ring of graphene and allowed the separated entangled electrons to stream into opposite pieces of artificial diamond. The carbon lattice of an artificial diamond contains traces of accidental nitrogen atoms in place of carbon and the gaps between the N and C atoms creates an environment called a 'hollow' which is attracting to electrons. This is the method they used to create a pair of diamonds containing opposite pairs of entangled electrons for their experiments in Delft. The entangled electrons are stable within the diamonds and they can be transported without disturbing the entanglement. Ghideon's example has nothing to do with entanglement. It is simply an example of changing the name of states with no physical interactions. The examples with boxes of socks and gloves are strictly classical and have been invalidated by Bell and the experiments by Aspect and Clauser and Zeilinger's teleportation would not work if the analogies were true. The idea that, "Some information is also encoded in the entanglement at that instant." implies the presence of a hidden variable. That has been debunked by the violation of Bell's inequality and double debunked by Henson et al.'s experiments in Delft.
  11. Your question made no sense. “Really? A real signal, i.e. transferring information (and therefore at least a minimum amount of energy)? Or will you beg the question, and will give entanglement as example? So, please, give an example of such a signal, but not concerning entanglement.” Your question is asking for, a real signal transferring information and energy but not entanglement. That is any ordinary signal. It could be a signal with a bell or a postal letter or a signal with flags. That can't be what your asking for. If you are asking for a signal without a transfer of energy, I gave you one and that is entanglement. If you want a signal with entanglement and a transfer of energy, I gave you one. If you want an example of a signal without a transfer of energy, I can't think of any example except entanglement. And if you want an example with exactly what you asked for, I just gave you three. And this post via computer is four.
  12. Henson’s experiments were made beyond light-like which means they were made beyond the reach of a light signal in order to close ‘locality loop’. In reverse of the usual practice, the emitters were beyond reach of a light signal with a single detector near but not exactly in the center. I am not confident enough to describe how Henson’s experiment works except to say that it involves a single photon detector to detect photons from two stationary sources that contain entangled electrons embedded in a diamond material. When illuminated by a laser, the diamonds emit streams of photons and vary rarely they emit a pair of entangled photons from a pair of entangled electrons. One photon simultaneously from two remote sources. A coincidence detector identifies the entangled photons and sends a ‘ring’ signal to the detector to start recording for a narrow window of time when the photons arrive. As I recall the spin states of the electrons is interpreted from the interference pattern of the photons since the photons are also entangled with the electrons. It’s complicated. Don't bother, the socks don't fit the widows.
  13. I agree this is a superb example. That was the worst explanation of entanglement I have ever seen. If that is entanglement, then Aspect and Clauser got the Nobel for discovering that entanglement is a matter of changing the names on particles. It doesn't know, why should It ? The quantum properties of both entangled particles are random and changing on both ends of the entanglement until one property of the two is measured. The particles can be widely separated, and because of the distance between them, one particle shouldn’t ‘know’ what is happening to its partner without some form of communication between them and time for the communication to reach it. If a pair of entangled electrons is generated and a one sent in one direction and the other is sent in another direction the measurement of a single property of one electron, the spin direction for example, instantly establishes the identity of both separated electrons and quantum properties of the two will be found to be anti-correlated. Even if the the electrons are far apart and before a light signal has time to reach the second electron to get the message and ‘know’ which property was observed and how it should be oriented. https://www.tudelft.nl/en/dossiers/loophole-free-bell-test-tu-delft-crowns-80-years-old-debate-on-nature-of-reality-einsteins-spooky-action-is-real “Quantum mechanics states that a particle such as an electron can be in two different states at the same time, and even in two different places, as long as it is not observed. This is called ‘superposition’ and it is a very counter-intuitive concept”, says lead scientist Professor Ronald Hanson. Hanson’s group works with trapped electrons, which have a tiny magnetic effect known as a “spin” that can be pointing up, or down, or - when in superposition - up and down at the same time. “Things get really interesting when two electrons become entangled. Both are then up and down at the same time, but when observed one will always be down and the other one up. They are perfectly correlated, when you observe one, the other one will always be opposite. That effect is instantaneous, even if the other electron is in a rocket at the other end of the galaxy”, says Hanson.
  14. Again use of vague concepts. What does 'grounded' mean here? That the experiment happens to be done in an inertial frame? How is that statement vague? 'Grounded' in the local reference frame means it is based upon the local reference frame or it uses the local reference frame. And don't you have the same usage in German 'auf gegrundet'? That is a bit of confusion that kept things going. I kept saying that outside observations have no effect on the results of the experiment while "joigus" and others kept saying that outside observers see events in a different order so no one can say which came first. I was thinking of the experiment only while "joigus" and some others were discussing an Alice and Bob type scenario where SR matters. That was an unfortunate confusion that never should have happened but it did. My arguments were based on the experiment and the particles involved so I kept insisting that the SR differences of outside observers have no effect on the results. It is not so simple. For one thing, as I have explained before, you have the wrong idea about what a "preferred frame of reference" is and why it is prohibited by SR. Can you define what you mean by a preferred frame of reference? Also consider this, if Alice is next to the detector on the far left and Bob is next to the detector on the far right and the entangled particles reach both detectors at measurably the same instant relative to their origin at the center. Alice will say the particle arrived at her detector first and Bob will say the particle arrived his detector first. This should indicate that they, like all outside observers, are not in exactly the same reference frame as the experiment itself so they are in no position to say which particle was detected first. Others, and if I recall you are among them, say it is impossible to say which came first because the observation is relative. This is essentially saying outside observers can affect the order of events. I say there has to be a first by some tiny amount of time and the particles know which was observed first. It is not for outside observers to decide. Yes, the detectors are space-like separated even if they are both visible. If they are beyond the range of a light signal, they are light-like separated. See the definitions from physics.stackexchange.com/questions below. Spacelike separation means that there exists a reference frame where the two events occur simultaneously, but in different places. Timelike separation means that there exists a reference frame where the two events occur at the same place, but at different times. Lightlike means that, well, light could travel between those points. You seem to be avoiding quite a few questions put to you, and just repeating the same things over and over again. Your question was strange but I did answer it. The detectors may be space-like separated but they are not light-like separated for the operators so nothing superluminal was required. The detectors are only light-like separated when the signal between them is superluminal. There are ways of changing the detectors at superluminal speeds like for experiments involving Wheeler’s delayed choice but that was not one of them. If anyone thinks I didn’t answer their question their response should be- as was yours, ‘You didn’t my question about...’ And if they didn’t like my answer they should explain why and not just repeat the same question expecting a different answer. That would save a lot of miscommunication. And don't complain, 'You didn't answer my question,' without explaining what it was and expect me to guess.
  15. No, a 'preferred frame of reference' is an unworkable cosmological reference frame. That is the kind of "preferred" frame that is prohibited. It's an unfortunate and confusing use of the word 'preferred'. This example should be non-controversial enough. https://newscenter.lbl.gov/2010/05/10/untangling-quantum-entanglement/ Previous experiments led by Graham Fleming, a physical chemist holding joint appointments with Berkeley Lab and UC Berkeley, pointed to quantum mechanical effects as the key to the ability of green plants, through photosynthesis, to almost instantaneously transfer solar energy from molecules in light harvesting complexes to molecules in electrochemical reaction centers. Now a new collaborative team that includes Fleming have identified entanglement as a natural feature of these quantum effects. When two quantum-sized particles, for example a pair of electrons, are “entangled,” any change to one will be instantly reflected in the other, no matter how far apart they might be. Though physically separated, the two particles act as a single entity.
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