1394:, makes it possible to divert that path away from its ordinary destination so that path effectively comes to a dead end. With the detour in operation, nothing can reach either detector by way of that path, so there can be no interference. With it switched off the path resumes its ordinary mode of action and passes through the second beam-splitter, making interference reappear. This arrangement does not actually insert and remove the second beam-splitter, but it does make it possible to switch from a state in which interference appears to a state in which interference cannot appear, and do so in the interval between light entering the first beam-splitter and light exiting the second beam-splitter. If photons had "decided" to enter the first beam-splitter as either waves or a particles, they must have been directed to undo that decision and to go through the system in their other guise, and they must have done so without any physical process being relayed to the entering photons or the first beam-splitter because that kind of transmission would be too slow even at the speed of light. Wheeler's interpretation of the physical results would be that in one configuration of the two experiments a single copy of the wavefunction of an entering photon is received, with 50% probability, at one or the other detectors, and that under the other configuration two copies of the wave function, traveling over different paths, arrive at both detectors, are out of phase with each other, and therefore exhibit interference. In one detector the wave functions will be in phase with each other, and the result will be that the photon has 100% probability of showing up in that detector. In the other detector the wave functions will be 180° out of phase, will cancel each other exactly, and there will be a 0% probability of their related photons showing up in that detector.
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that the two wavefunctions for each photon will be in superposition within a fairly short distance from the double slits, and if a detection screen is provided within the region wherein the wavefunctions are in superposition then interference patterns will be seen. There is no way by which any given photon could have been determined to have arrived from one or the other of the double slits. However, if the detection screen is removed the wavefunctions on each path will superimpose on regions of lower and lower amplitudes, and their combined probability values will be much less than the unreinforced probability values at the center of each path. When telescopes are aimed to intercept the center of the two paths, there will be equal probabilities of nearly 50% that a photon will show up in one of them. When a photon is detected by telescope 1, researchers may associate that photon with the wavefunction that emerged from the lower slit. When one is detected in telescope 2, researchers may associate that photon with the wavefunction that emerged from the upper slit. The explanation that supports this interpretation of experimental results is that a photon has emerged from one of the slits, and that is the end of the matter. A photon must have started at the laser, passed through one of the slits, and arrived by a single straight-line path at the corresponding telescope.
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galaxy. At that point it would have to "decide" whether to go by one way around the lensing galaxy, traveling as a particle, or go both ways around by traveling as a wave. When the photon arrived at an astronomical observatory at Earth, what would happen? Due to the gravitational lensing, telescopes in the observatory see two images of the same quasar, one to the left of the lensing galaxy and one to the right of it. If the photon has traveled as a particle and comes into the barrel of a telescope aimed at the left quasar image it must have decided to travel as a particle all those millions of years, or so say some experimenters. That telescope is pointing the wrong way to pick up anything from the other quasar image. If the photon traveled as a particle and went the other way around, then it will only be picked up by the telescope pointing at the right "quasar." So millions of years ago the photon decided to travel in its guise of particle and randomly chose the other path. But the experimenters now decide to try something else. They direct the output of the two telescopes into a beam-splitter, as diagrammed, and discover that one output is very bright (indicating positive interference) and that the other output is essentially zero, indicating that the incoming wavefunction pairs have self-cancelled.
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only hitting the detector on the right. This is explained if in this configuration the photon travels as a wave along both paths. The trajectory that ends at the detector at the top combines one route in which the wave is reflected on both beam splitters, with another in which it is transmitted through both of them. This introduces a difference in length between the two routes that causes the wave to be out of phase with itself and cancel out (destructive interference) as it leaves the second beam splitter towards the detector at the top. The trajectory to the detector on the right, on the other hand, involves two identical routes --two reflections and two transmissions at the splitters -- which causes their phases to match, hence the waves reinforce each other (constructive interference) and always hit this detector. This happens even if only one photon is emitted at a time, which means the photon travels as a wave along both paths and interferes with itself as only a wave can do.
1350:, pp 182–213. He introduced his remarks by reprising the argument between Albert Einstein, who wanted a comprehensible reality, and Niels Bohr, who thought that Einstein's concept of reality was too restricted. Wheeler indicates that Einstein and Bohr explored the consequences of the laboratory experiment that will be discussed below, one in which light can find its way from one corner of a rectangular array of semi-silvered and fully silvered mirrors to the other corner, and then can be made to reveal itself not only as having gone halfway around the perimeter by a single path and then exited, but also as having gone both ways around the perimeter and then to have "made a choice" as to whether to exit by one port or the other. Not only does this result hold for beams of light, but also for single photons of light. Wheeler remarked:
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particle feature manifests itself long after—and even space-like separated from—the measurement teaches us that we should not have any naive realistic picture for interpreting quantum phenomena. Any explanation of what goes on in a specific individual observation of one photon has to take into account the whole experimental apparatus of the complete quantum state consisting of both photons, and it can only make sense after all information concerning complementary variables has been recorded. Our results demonstrate that the viewpoint that the system photon behaves either definitely as a wave or definitely as a particle would require faster-than-light communication. Because this would be in strong tension with the special theory of relativity, we believe that such a viewpoint should be given up entirely.
1032:. Because of the equal probabilities for transmission or reflection the photon will either continue straight ahead, be reflected by the mirror at the lower-right corner, and be detected by the detector at the top of the apparatus (indicated by the blue path), or it will be reflected by the beam splitter, strike the mirror in the upper-left corner, and emerge into the detector at the right edge of the apparatus (red path). To explain the observation that photons show up in equal numbers at the two detectors, but never at both at a time, one hypothesis says that each photon has behaved as a particle from the time of its emission to the time of its detection, has traveled by either one path or the other, and its wave nature has not been exhibited.
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arrive by two pathways. Depending on how phase differences between wavefunction pairs are arranged, correspondingly different kinds of interference phenomena can be observed. Whether to merge the incoming wavefunctions or not, and how to merge the incoming wavefunctions can be controlled by experimenters. There are none of the phase differences introduced into the wavefunctions by the experimental apparatus as there are in the laboratory interferometer experiments, so despite there being no double-slit device near the light source, the cosmic experiment is closer to the double-slit experiment. However, Wheeler planned for the experiment to merge the incoming wavefunctions by use of a beam splitter.
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configuration that would call for it to show its particle nature but ends up in an experimental configuration that would call for it to show its wave nature, it will always show its wave characteristics by interfering with itself. Likewise, if the experiment began with the second beam splitter in place but it was removed while the photon was in flight, then the photon would inevitably hit either detector without any sign of interference effects. So the presence or absence of the second beam splitter would always determine if it has "wave or particle" manifestation. Many experimenters reached an interpretation of the experimental results that said that the change in final conditions would
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choice of type of phenomenon to be looked for up to the very final stage of development of the phenomenon, and it depends on whichever type of detection device we then fix upon. That delay makes no difference in the experimental predictions. On this score everything we find was foreshadowed in that solitary and pregnant sentence of Bohr, "...it...can make no difference, as regards observable effects obtainable by a definite experimental arrangement, whether our plans for constructing or handling the instruments are fixed beforehand or whether we prefer to postpone the completion of our planning until a later moment when the particle is already on its way from one instrument to another."
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the photon source to a position where the distance between the two copies of the wavefunction is too great to show interference effects. The technical problem in the laboratory is how to insert a detector screen at a point appropriate to observe interference effects or to remove that screen to reveal the photon detectors that can be restricted to receiving photons from the narrow regions of space where the slits are found. One way to accomplish that task would be to use the recently developed electrically switchable mirrors and simply change directions of the two paths from the slits by switching a mirror on or off. As of early 2014 no such experiment has been announced.
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as a particle, and then quickly let the second beam splitter pop up into its path? Having presumably traveled as a particle up to that moment, would the beam splitter let it pass through and manifest itself as would a particle as if that second beam splitter had not been there? Or, would it behave as though the second beam splitter had always been there? Would it manifest interference effects? And if it did manifest interference effects, then to have done so must it have gone back in time and changed its "decision" about traveling as a particle to traveling as a wave? Note that
Wheeler wanted to investigate several hypotheses by obtaining objective data.
1358:, discussed by Einstein and Bohr, could theoretically be used to investigate whether a photon sometimes sets off along a single path, always follows two paths but sometimes only makes use of one, or whether something else would turn up. However, it was easier to say, "We will, during random runs of the experiment, insert the second half-silvered mirror just before the photon is timed to get there," than it was to figure out a way to make such a rapid substitution. The speed of light is just too fast to permit a mechanical device to do this job, at least within the confines of a laboratory. Much ingenuity was needed to get around this problem.
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photon decide whether it is going to travel as a wave or as a particle? Suppose that a traditional double-slit experiment is prepared so that either of the slits can be blocked. If both slits are open and a series of photons are emitted by the laser then an interference pattern will quickly emerge on the detection screen. The interference pattern can only be explained as a consequence of wave phenomena, so experimenters may conclude that each photon "decided" to travel as a
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create another change in the system that would make it seem that the photon had "chosen" to behave in the opposite way. Some interpreters of these experiments contend that a photon either is a wave or is a particle, and that it cannot be both at the same time. Wheeler's intent was to investigate the time-related conditions under which a photon makes this transition between alleged states of being. His work has been productive of many revealing experiments.
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972:. Which characteristic is measured depends on whether experimenters use a device intended to observe particles or to observe waves. When this statement is applied very strictly, one could argue that by determining the detector type one could force the photon to become manifest only as a particle or only as a wave. Detection of a photon is generally a destructive process (see
984:, a photon appears as a highly localized point in space and time on a screen. The buildup of the photons on the screen gives an indication on whether the photon must have traveled through the slits as a wave or could have traveled as a particle. The photon is said to have traveled as a wave if the buildup results in the typical interference pattern of waves (see
1270:. The surprising implications of the original delayed-choice experiment led Wheeler to the conclusion that "no phenomenon is a phenomenon until it is an observed phenomenon". Wheeler famously said that the "past has no existence except as recorded in the present", and that the Universe does not "exist, out there independent of all acts of observation".
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diaphragm must have "decided" that it needs to go through both slits to be able to interfere with itself on the detection screen. For no interference to be manifested, a single photon coming into the double-slit diaphragm must have "decided" to go by only one slit because that would make it show up at the camera in the appropriate single telescope.
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location provided for the second beam-splitter. This realization of the experiment is done by extending the lengths of both paths by inserting long lengths of fiber optic cable. So doing makes the time interval involved with transits through the apparatus much longer. A high-speed switchable device on one path, composed of a high-voltage switch, a
1367:, involving a triggered diamond N–V colour centre photon generator, polarization, and an electro-optical modulator acting as a switchable beam splitter. Measuring in a closed configuration showed interference, while measuring in an open configuration allowed the path of the particle to be determined, which made interference impossible.
1337:). The book PVMM referred to above makes the important observation (sec. 6.7.1) that the quantum potential contains information about the boundary conditions defining the system, and hence any change of the experimental set up is immediately recognized by the quantum potential, and determines the dynamics of the Bohmian particle.
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just after the photon leaves the diaphragm. Some theorists argue that inserting or removing the screen in the midst of the experiment can force a photon to retroactively decide to go through the double-slits as a particle when it had previously transited it as a wave, or vice versa. Wheeler does not accept this interpretation.
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Kundić, Tomislav; Turner, Edwin L; Colley, Wesley N; Gott Iii, J. Richard; Rhoads, James E; Wang, Yun; Bergeron, Louis E; Gloria, Karen A; Long, Daniel C; Malhotra, Sangeeta; Wambsganss, Joachim (1997). "A Robust
Determination of the Time Delay in 0957+561A, B and a Measurement of the Global Value of
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Wheeler's version of the double-slit experiment is arranged so that the same photon that emerges from two slits can be detected in two ways. The first way lets the two paths come together, lets the two copies of the wavefunction overlap, and shows interference. The second way moves farther away from
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and the possibility of identifying identical events of some signal characteristic. Information from the Twin
Quasars that Wheeler used as the basis of his speculation reach earth approximately 14 months apart. Finding a way to keep a quantum of light in some kind of loop for over a year would not be
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The double slit experiment, like the other six idealized experiments (microscope, split beam, tilt-teeth, radiation pattern, one-photon polarization, and polarization of paired photons), imposes a choice between complementary modes of observation. In each experiment we have found a way to delay that
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In this thought experiment the telescopes are always present, but the experiment can start with the detection screen being present but then being removed just after the photon leaves the double-slit diaphragm, or the experiment can start with the detection screen being absent and then being inserted
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Wheeler then plays the devil's advocate and suggests that perhaps for those experimental results to be obtained would mean that at the instant astronomers inserted their beam-splitter, photons that had left the quasar some millions of years ago retroactively decided to travel as waves, and that when
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That is, when the presence of a second beam splitter makes both paths reach both detectors, thus rendering their paths indistinguishable, the photon shows the wave characteristic of interference. Otherwise, it will randomly hit one detector or the other, as would a particle coming from just one path
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This line of experimentation proved very difficult to carry out when it was first conceived. Nevertheless, it has proven very valuable over the years since it has led researchers to provide "increasingly sophisticated demonstrations of the wave–particle duality of single quanta". As one experimenter
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However Bohm et al. (1985, Nature vol. 315, pp. 294–97) have shown that the
Bohmian interpretation gives a straightforward account of the behaviour of the particle under the delayed-choice set up. A detailed discussion is available in the open-source article by Basil Hiley and Callaghan, while
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A second kind of experiment resembles the ordinary double-slit experiment. The schematic diagram of this experiment shows that a lens on the far side of the double slits makes the path from each slit diverge slightly from the other after they cross each other fairly near to that lens. The result is
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In an attempt to avoid destroying normal ideas of cause and effect, some theoreticians suggested that information about whether there was or was not a second beam-splitter installed could somehow be transmitted from the end point of the experimental device back to the photon as it was just entering
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Albert
Einstein did not like these possible consequences of quantum mechanics. However, when experiments were finally devised that permitted both the double-slit version and the interferometer version of the experiment, it was conclusively shown that a photon that begins its life in an experimental
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Thus, Wheeler wanted to know if, experimentally, a time could be determined at which the photon made its "decision." Would it be possible to let a photon pass through the region of the first beam splitter while there was no beam splitter in the second position, thus causing it to "decide" to travel
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for an animation showing the buildup). However, if one of the slits is closed, or two orthogonal polarizers are placed in front of the slits (making the photons passing through different slits distinguishable), then no interference pattern will appear, and the buildup can be explained as the result
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The cosmic experiment envisioned by
Wheeler could be described either as analogous to the interferometer experiment or as analogous to a double-slit experiment. The important thing is that by a third kind of device, a massive stellar object acting as a gravitational lens, photons from a source can
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Several ways of implementing
Wheeler's basic idea have been made into real experiments and they support the conclusion that Wheeler anticipated — that what is done at the exit port of the experimental device before the photon is detected will determine whether it displays interference phenomena or
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or other galaxy millions or billions of light years away from Earth passes its light around an intervening galaxy or cluster of galaxies that would act as a gravitational lens. A photon heading exactly towards Earth would encounter the distortion of space in the vicinity of the intervening massive
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The common intention of these several types of experiments is to first do something that, according to some hidden-variable models, would make each photon "decide" whether it were going to behave as a particle or behave as a wave, and then, before the photon had time to reach the detection device,
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If the apparatus is changed so that a second beam splitter is placed in the upper-right corner and the mirrors and splitters adjusted precisely at the same distance between one another, then the photons from each path will recombine at the second beam splitter and will show interference by always
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Quantum mechanics predicts that the photon always travels as a wave, however, one can only see this prediction by detecting the photon as a particle. Thus, the question arises: Could the photon decide to travel as a wave or a particle depending on the experimental setup? And if yes, when does the
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The
Wheeler version of the interferometer experiment could not be performed in a laboratory until recently because of the practical difficulty of inserting or removing the second beam-splitter in the brief time interval between the photon's entering the first beam-splitter and its arrival at the
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The main difficulty in performing this experiment is that the experimenter has no control over or knowledge of when each photon began its trip toward earth, and the experimenter does not know the lengths of each of the two paths between the distant quasar. Therefore, it is possible that the two
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information or an interference pattern of one (system) photon depends on the choice of measurement on the other (environment) photon, even when all of the events on the two sides that can be space-like separated are space-like separated. The fact that it is possible to decide whether a wave or
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The cosmic experiment described by
Wheeler has other problems, but directing wavefunction copies to one place or another long after the photon involved has presumably "decided" whether to be a wave or a particle requires no great speed at all. One has about a billion years to get the job done.
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The retrocausal explanation, which
Wheeler does not accept, says that with the detection screen in place, interference must be manifested. For interference to be manifested, a light wave must have emerged from each of the two slits. Therefore, a single photon upon coming into the double-slit
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copies of one wavefunction might well arrive at different times. Matching them in time so that they could interact would require using some kind of delay device on the first to arrive. Before that task could be done, it would be necessary to find a way to calculate the time delay.
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In such experiments, Einstein originally argued, it is unreasonable for a single photon to travel simultaneously two routes. Remove the half-silvered mirror at the , and one will find that the one counter goes off, or the other. Thus the photon has traveled only
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the astronomers decided to pull their beam splitter out again that decision was telegraphed back through time to photons that were leaving some millions of years plus some minutes in the past, so that photons retroactively decided to travel as particles.
1285:. A photon or an electron has a definite trajectory and passes through one or the other of the two slits and not both, just as it is in the case of a classical particle. The past is determined and stays what it was up to the moment
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it travels through, adjusting its behavior to fit by assuming an appropriate determinate state, or whether light remains in an indeterminate state, exhibiting both wave-like and particle-like behavior until measured.
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John Archibald Wheeler, ""The'Past" and the 'Delayed Choice' Double-Slit experiment," which appeared in 1978 and has been reprinted is several locations, e.g. Lisa M. Dolling, Arthur F. Gianelli, Glenn N. Statilem,
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Ma, Xiao-Song; Kofler, Johannes; Qarry, Angie; Tetik, Nuray; Scheidl, Thomas; Ursin, Rupert; Ramelow, Sven; Herbst, Thomas; Ratschbacher, Lothar; Fedrizzi, Alessandro; Jennewein, Thomas; Zeilinger, Anton (2013).
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Ma, Xiao-Song; Kofler, Johannes; Qarry, Angie; Tetik, Nuray; Scheidl, Thomas; Ursin, Rupert; Ramelow, Sven; Herbst, Thomas; Ratschbacher, Lothar; Fedrizzi, Alessandro; Jennewein, Thomas; Zeilinger, Anton (2013).
1630:, edited by A. R. Marlow, Academic Press, 1978. P. 39 lists seven experiments: double slit, microscope, split beam, tilt-teeth, radiation pattern, one-photon polarization, and polarization of paired photons.
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when it is detected as a particle. Thus Bohmian mechanics restores the conventional view of the world and its past. The past is out there as an objective history unalterable retroactively by delayed choice.
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Jacques, Vincent; Wu, E; Grosshans, Frédéric; Treussart, François; Grangier, Philippe; Aspect, Alain; Roch, Jean-François (2007). "Experimental Realization of Wheeler's Delayed-Choice Gedanken Experiment".
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After several supporting experiments were published, Jacques et al. claimed that an experiment of theirs follows fully the original scheme proposed by Wheeler. Their complicated experiment is based on the
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John Wheeler's original discussion of the possibility of a delayed choice quantum appeared in an essay entitled "Law Without Law," which was published in a book he and Wojciech Hubert Zurek edited called
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For Niels Bohr... this "central mystery" was ...a principle of the ... complementarity principle. .... Look for a particle and you'll see a particle. Look for a wave and that's what you'll see.
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that experimental device, thus permitting it to make the proper "decision." So Wheeler proposed a cosmic version of his experiment. In that thought experiment he asks what would happen if a
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route. It travels only one route. but it travels both routes: it travels both routes, but it travels only one route. What nonsense! How obvious it is that quantum theory is inconsistent!
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would; it follows that the photon seems to "decide" whether it will travel through the interferometer as a particle or as a wave depending on the setup that it will encounter
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as soon as it was emitted. If only one slit is available then there will be no interference pattern, so experimenters may conclude that each photon "decided" to travel as a
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920:, with the most prominent among them appearing in 1978 and 1984. These experiments are attempts to decide whether light somehow "senses" the experimental apparatus in the
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The first real experiment to follow Wheeler's intention for a double-slit apparatus to be subjected to end-game determination of detection method is the one by Walborn
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957:. Many of them are discussed in Wheeler's 1978 article "The 'Past' and the 'Delayed-Choice' Double-Slit Experiment", which has been reproduced in A. R. Marlow's
953:, the first being proposed by him in 1978. Another prominent version was proposed in 1983. All of these experiments try to get at the same fundamental issues in
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1314:, when the experimental set up was changed, Bohm's quantum potential changes as needed, and the particle moves classically under the new quantum potential till
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This experiment uses Bell inequalities to replace the delayed choice devices, but it achieves the same experimental purpose in an elegant and convincing way.
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Kaiser, Florian; Coudreau, Thomas; Milman, PĂ©rola; Ostrowsky, Daniel B.; Tanzilli, SĂ©bastien (2012). "Entanglement-Enabled Delayed-Choice Experiment".
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determine what the photon had "decided" to be as it was entering the first beam splitter. As mentioned above, Wheeler rejected this interpretation.
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The cosmic version of the interferometer experiment could be adapted to function as a cosmic double-slit device as indicated in the illustration.
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In Bohm's quantum mechanics, the particle obeys classical mechanics except that its movement takes place under the additional influence of its
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that accepts its energy, which is then used to trigger the cascade of events that produces a "click" from that device. In the case of the
1992:"No reasonable definition of reality could be expected to permit this," huffed in a famous paper ... (Physical Review, vol 47, p 777).
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Peruzzo, Alberto; Shadbolt, Peter; Brunner, Nicolas; Popescu, Sandu; O'Brien, Jeremy L (2012). "A Quantum Delayed-Choice Experiment".
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for non-destructive measurements). For example, a photon can be detected as the consequences of being absorbed by an electron in a
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One suggestion for synchronizing inputs from the two ends of this cosmic experimental apparatus lies in the characteristics of
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Double quasar known as QSO 0957+561, also known as the "Twin Quasar", which lies just under 9 billion light-years from Earth.
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John Archibald Wheeler, "The 'Past' and the 'Delayed-Choice Double-Slit Experiment'," pp 9–48, in A.R. Marlow, editor,
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The "quantum potential" Q(r,T) is often taken to act instantly. But in fact, the change of the experimental set up at T
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Jacques, Vincent; et al. (2007). "Experimental Realization of Wheeler's Delayed-Choice Gedanken Experiment".
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have summarized what can be known as a result of experiments that have arisen from Wheeler's proposals. They say:
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research have explicated the practical difficulties of conducting the interstellar Wheeler experiment.
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as soon as it was emitted. Notably however, in either case the photon must commit to its decision
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Hiley, B.J.; Callaghan, Robert (2006-08-09). "Delayed Choice Experiments and the Bohm Approach".
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Edward G. Steward, Quantum Mechanics: Its Early Development and the Road to Entanglement, p. 145.
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Walborn, S. P; Terra Cunha, M. O; Pádua, S; Monken, C. H (2002). "Double-slit quantum eraser".
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30:
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1427:
Replace beam splitter by registering projected telescope images on a common detection screen.
3011:
3006:
2863:
2744:
2444:
2434:
2382:
2324:
2269:
2236:
2136:
2074:
1938:
1866:
1811:
1801:
1735:
1684:
1541:
838:
828:
818:
718:
698:
683:
653:
521:
409:
1235:
3241:
3168:
3148:
3118:
3081:
3076:
2981:
2805:
977:
954:
950:
913:
863:
733:
713:
459:
299:
1333:) changes slowly over the time interval dT to become the new quantum potential Q(r,T>T
17:
2430:
2378:
2320:
2232:
2132:
1924:
1862:
1797:
1713:
1680:
1537:
1464:
confirms the standard predictions of standard quantum mechanics with an atom of Helium.
3219:
3188:
3178:
2800:
2780:
2609:
2449:
2404:
1816:
1771:
1655:"Proposal to test quantum wave-particle superposition on massive mechanical resonators"
1355:
798:
758:
738:
708:
688:
638:
604:
454:
444:
237:
2099:
Chandré Dharma-wardana, A Physicist's View of matter and Mind (World Scientific, 2013)
1274:
many of the quantum paradoxes including delayed choice are summarized in Chapter 7 of
1197:
3317:
3138:
2991:
2882:
2785:
2701:
2671:
2624:
2263:
2078:
1029:
858:
853:
783:
753:
723:
594:
540:
267:
242:
2336:
2086:
1958:
1755:
3021:
2619:
2614:
2248:
2156:
1886:
1653:
Qin, Wei; Miranowicz, Adam; Long, Guilu; You, J. Q.; Nori, Franco (December 2019).
1568:
1561:
1387:
1020:
848:
843:
778:
763:
728:
222:
2172:, by John Archibald Wheeler with Kenneth Ford, W.W. Norton & Co., 1998, p. 337
2004:
1739:
3059:
2480:
1423:
1077:
813:
768:
703:
658:
2328:
1064:
2491:
2273:
1689:
1654:
803:
773:
693:
668:
663:
648:
1747:
1698:
120:{\displaystyle i\hbar {\frac {d}{dt}}|\Psi \rangle ={\hat {H}}|\Psi \rangle }
2913:
2594:
2439:
2140:
1942:
1870:
1806:
1545:
294:
2458:
2148:
2123:
1950:
1878:
1825:
1553:
2311:
2223:
1528:
673:
1589:
Science and Ultimate Reality: Quantum Theory, Cosmology, and Complexity
2387:
2362:
1411:
1207:
2506:
1453:
Researchers with access to radio telescopes originally designed for
986:
Double-slit experiment § Interference from individual particles
2240:
2069:
1671:
933:
explains, "Wave and particle behavior can coexist simultaneously."
2485:
2421:
2361:
Manning, A. G; Khakimov, R. I; Dall, R. G; Truscott, A. G (2015).
1915:
1853:
1788:
1730:
1607:
1422:
1234:
1213:
1196:
1019:
29:
2363:"Wheeler's delayed-choice gedanken experiment with a single atom"
1712:
Ma, Xiao-song; Kofler, Johannes; Zeilinger, Anton (2016-03-03).
1454:
2510:
1587:
John D. Barrow, Paul C. W. Davies, and Jr, Charles L. Harperm
1137:
1071:
1714:"Delayed-choice gedanken experiments and their realizations"
2350:
Quantum Astronomy (IV): Cosmic-Scale Double-Slit Experiment
2476:
Wheeler's Classic Delayed Choice Experiment by Ross Rhodes
1600:
Delayed-choice gedanken experiments and their realizations
1292:
when the experimental configuration for detecting it as a
2492:"John Wheeler - The Delayed Choice experiment (105/130)"
2170:
Geons, Black Holes & Quantum Foam: A Life in Physics
1329:
takes a finite time dT. The initial potential Q(r,T<T
1278:(PVMM) using both Bohmian and standard interpretations.
1017:. The apparatus is depicted in the image to the right.
1218:
Paths separated and paths converged via beam-splitter
58:
1598:
Xiao-song Ma, Johannes Kofler, and Anton Zeilinger,
3255:
3207:
3040:
2972:
2906:
2819:
2768:
2722:
2587:
2544:
2405:"Quantum erasure with causally disconnected choice"
1772:"Quantum erasure with causally disconnected choice"
1569:
On-line bibliography listing all of Wheeler's works
1580:John Archibald Wheeler and Wojciech Hubert Zurek,
1005:encountering the actual configured slit scenario.
119:
2409:Proceedings of the National Academy of Sciences
1776:Proceedings of the National Academy of Sciences
2043:Readings in the Development of Physical Theory
2522:
886:
27:Number of quantum physics thought experiments
8:
1165:. There might be a discussion about this on
114:
88:
2486:Demystifying the Delayed Choice Experiments
1106:. Unsourced material may be challenged and
2529:
2515:
2507:
2029:Mathematical Foundations of Quantum Theory
1628:Mathematical Foundations of Quantum Theory
1575:Mathematical Foundations of Quantum Theory
959:Mathematical Foundations of Quantum Theory
893:
879:
37:
2448:
2438:
2420:
2386:
2310:
2222:
2122:
2068:
1932:
1914:
1852:
1815:
1805:
1787:
1729:
1688:
1670:
1527:
1185:Learn how and when to remove this message
1126:Learn how and when to remove this message
106:
95:
94:
80:
65:
57:
3324:Thought experiments in quantum mechanics
1063:
1620:
989:of the photon traveling as a particle.
62:
45:
1639:George Greenstein and Arthur Zajonc,
1501:Wheeler–Feynman time-symmetric theory
1276:A Physicist's View of Matter and Mind
7:
2481:The Quantum Eraser by John G. Cramer
1104:adding citations to reliable sources
2268:. New York, NY: Springer New York.
1296:was changed to that of detecting a
943:Wheeler's delayed-choice experiment
906:Wheeler's delayed-choice experiment
2498:. Web of Stories. 6 October 2017.
1227:not. Retrocausality is a mirage.
425:Sum-over-histories (path integral)
111:
85:
41:Part of a series of articles about
25:
974:quantum nondemolition measurement
3298:
3297:
2502:from the original on 2021-12-21.
1239:Wheeler's double-slit apparatus.
1142:
1076:
2031:, edited by A.R. Marlow, p. 13
1984:, 07 January 2–13, p. 1f says:
1460:A recent experiment by Manning
1443:Current experiments of interest
3247:Relativistic quantum mechanics
2009:ESA/Hubble Picture of the Week
1610:, March 2016. Survey article.
1582:Quantum Theory and Measurement
1419:Double-slits in lab and cosmos
1354:The experiment in the form an
1348:Quantum Theory and Measurement
575:Relativistic quantum mechanics
107:
100:
81:
1:
3225:Quantum statistical mechanics
3002:Quantum differential calculus
2924:Delayed-choice quantum eraser
2692:Symmetry in quantum mechanics
1584:(Princeton Series in Physics)
1496:Delayed-choice quantum eraser
970:but not both at the same time
615:Quantum statistical mechanics
2265:Epistemology and Probability
1740:10.1103/RevModPhys.88.015005
1398:Interferometer in the cosmos
3027:Quantum stochastic calculus
3017:Quantum measurement problem
2939:Mach–Zehnder interferometer
2262:Plotnitsky, Arkady (2010).
1365:Mach–Zehnder interferometer
1015:Mach–Zehnder interferometer
585:Quantum information science
3340:
2329:10.1103/PhysRevA.65.033818
2079:10.1088/0031-8949/74/3/007
1593:Cambridge University Press
3293:
3087:Quantum complexity theory
3065:Quantum cellular automata
2755:Path integral formulation
2274:10.1007/978-0-387-85334-5
2211:The Astrophysical Journal
1718:Reviews of Modern Physics
1690:10.1038/s41534-019-0172-9
1381:Interferometer in the lab
966:complementarity principle
18:Delayed choice experiment
3154:Quantum machine learning
3134:Quantum key distribution
3124:Quantum image processing
3114:Quantum error correction
2964:Wheeler's delayed choice
945:" refers to a series of
620:Quantum machine learning
373:Wheeler's delayed-choice
3070:Quantum finite automata
2440:10.1073/pnas.1213201110
2194:Greenstein and Zajonc,
2181:Greenstein and Zajonc,
2141:10.1126/science.1136303
1943:10.1126/science.1226755
1871:10.1126/science.1226719
1807:10.1073/pnas.1213201110
1659:npj Quantum Information
1577:, Academic Press (1978)
1546:10.1126/science.1136303
330:Leggett–Garg inequality
3174:Quantum neural network
1994:
1989:
1487:
1428:
1378:
1360:
1262:Bohmian interpretation
1259:
1240:
1219:
1202:
1069:
1025:
982:double-slit experiment
922:double-slit experiment
918:John Archibald Wheeler
908:describes a family of
121:
35:
3199:Quantum teleportation
2712:Wave–particle duality
2196:The Quantum Challenge
2183:The Quantum Challenge
1990:
1985:
1641:The Quantum Challenge
1478:
1426:
1369:
1352:
1254:
1238:
1217:
1200:
1067:
1060:Cosmic interferometer
1023:
1009:Simple interferometer
315:Elitzur–Vaidman
305:Davisson–Germer
122:
33:
3230:Quantum field theory
3159:Quantum metamaterial
3104:Quantum cryptography
2834:Consistent histories
2209:Hubble's Constant".
1341:Experimental details
1300:at the arrival time
1155:confusing or unclear
1100:improve this section
580:Quantum field theory
492:Consistent histories
129:Schrödinger equation
56:
3215:Quantum fluctuation
3184:Quantum programming
3144:Quantum logic gates
3129:Quantum information
3109:Quantum electronics
2569:Classical mechanics
2431:2013PNAS..110.1221M
2379:2015NatPh..11..539M
2321:2002PhRvA..65c3818W
2233:1997ApJ...482...75K
2133:2007Sci...315..966J
1980:Anil Ananthaswamy,
1925:2012Sci...338..637K
1863:2012Sci...338..634P
1798:2013PNAS..110.1221M
1681:2019npjQI...5...58Q
1538:2007Sci...315..966J
1392:Glan–Thompson prism
1231:Double-slit version
1163:clarify the article
947:thought experiments
910:thought experiments
368:Stern–Gerlach
165:Classical mechanics
3268:in popular culture
3050:Quantum algorithms
2898:Von Neumann–Wigner
2878:Objective collapse
2574:Old quantum theory
2124:quant-ph/0610241v1
1429:
1241:
1220:
1203:
1070:
1026:
556:Von Neumann–Wigner
536:Objective-collapse
335:Mach–Zehnder
325:Leggett inequality
320:Franck–Hertz
170:Old quantum theory
117:
36:
34:John Wheeler, 1985
3311:
3310:
3285:Quantum mysticism
3263:Schrödinger's cat
3194:Quantum simulator
3164:Quantum metrology
3092:Quantum computing
3055:Quantum amplifier
3032:Quantum spacetime
2997:Quantum cosmology
2987:Quantum chemistry
2687:Scattering theory
2635:Zero-point energy
2630:Degenerate levels
2538:Quantum mechanics
2388:10.1038/nphys3343
2299:Physical Review A
2283:978-0-387-85333-8
2117:(5814): 966–968.
1909:(6107): 637–640.
1847:(6107): 634–637.
1283:quantum potential
1268:Bohmian mechanics
1195:
1194:
1187:
1136:
1135:
1128:
964:According to the
961:, pp. 9–48.
903:
902:
610:Scattering theory
590:Quantum computing
363:Schrödinger's cat
295:Bell's inequality
103:
78:
47:Quantum mechanics
16:(Redirected from
3331:
3301:
3300:
3012:Quantum geometry
3007:Quantum dynamics
2864:Superdeterminism
2796:Rarita–Schwinger
2745:Matrix mechanics
2600:Bra–ket notation
2531:
2524:
2517:
2508:
2503:
2463:
2462:
2452:
2442:
2424:
2415:(4): 1221–1226.
2399:
2393:
2392:
2390:
2358:
2352:
2347:
2341:
2340:
2314:
2312:quant-ph/0106078
2294:
2288:
2287:
2259:
2253:
2252:
2226:
2224:astro-ph/9610162
2205:
2199:
2192:
2186:
2179:
2173:
2167:
2161:
2160:
2126:
2106:
2100:
2097:
2091:
2090:
2072:
2052:
2046:
2038:
2032:
2026:
2020:
2019:
2017:
2015:
2001:
1995:
1978:
1972:
1969:
1963:
1962:
1936:
1918:
1898:
1892:
1890:
1856:
1836:
1830:
1829:
1819:
1809:
1791:
1766:
1760:
1759:
1733:
1709:
1703:
1702:
1692:
1674:
1650:
1644:
1637:
1631:
1625:
1565:
1531:
1529:quant-ph/0610241
1190:
1183:
1179:
1176:
1170:
1146:
1145:
1138:
1131:
1124:
1120:
1117:
1111:
1080:
1072:
1042:at the end of it
895:
888:
881:
522:Superdeterminism
175:Bra–ket notation
126:
124:
123:
118:
110:
105:
104:
96:
84:
79:
77:
66:
38:
21:
3339:
3338:
3334:
3333:
3332:
3330:
3329:
3328:
3314:
3313:
3312:
3307:
3289:
3275:Wigner's friend
3251:
3242:Quantum gravity
3203:
3189:Quantum sensing
3169:Quantum network
3149:Quantum machine
3119:Quantum imaging
3082:Quantum circuit
3077:Quantum channel
3036:
2982:Quantum biology
2968:
2944:Elitzur–Vaidman
2919:Davisson–Germer
2902:
2854:Hidden-variable
2844:de Broglie–Bohm
2821:Interpretations
2815:
2764:
2718:
2605:Complementarity
2583:
2540:
2535:
2490:
2472:
2467:
2466:
2401:
2400:
2396:
2360:
2359:
2355:
2348:
2344:
2296:
2295:
2291:
2284:
2261:
2260:
2256:
2207:
2206:
2202:
2193:
2189:
2180:
2176:
2168:
2164:
2108:
2107:
2103:
2098:
2094:
2057:Physica Scripta
2054:
2053:
2049:
2039:
2035:
2027:
2023:
2013:
2011:
2005:"Seeing double"
2003:
2002:
1998:
1979:
1975:
1970:
1966:
1934:10.1.1.592.8022
1900:
1899:
1895:
1838:
1837:
1833:
1782:(4): 110–1226.
1768:
1767:
1763:
1711:
1710:
1706:
1652:
1651:
1647:
1638:
1634:
1626:
1622:
1617:
1522:(5814): 966–8.
1512:
1509:
1492:
1470:
1445:
1421:
1400:
1383:
1343:
1336:
1332:
1328:
1320:
1313:
1306:
1291:
1264:
1233:
1191:
1180:
1174:
1171:
1160:
1147:
1143:
1132:
1121:
1115:
1112:
1097:
1081:
1062:
1024:Open and closed
1011:
978:photomultiplier
955:quantum physics
951:quantum physics
939:
914:quantum physics
899:
870:
869:
868:
633:
625:
624:
570:
569:Advanced topics
562:
561:
560:
512:Hidden-variable
502:de Broglie–Bohm
481:
479:Interpretations
471:
470:
469:
439:
431:
430:
429:
387:
379:
378:
377:
344:
300:CHSH inequality
289:
281:
280:
279:
208:Complementarity
202:
194:
193:
192:
160:
131:
70:
54:
53:
28:
23:
22:
15:
12:
11:
5:
3337:
3335:
3327:
3326:
3316:
3315:
3309:
3308:
3306:
3305:
3294:
3291:
3290:
3288:
3287:
3282:
3277:
3272:
3271:
3270:
3259:
3257:
3253:
3252:
3250:
3249:
3244:
3239:
3238:
3237:
3227:
3222:
3220:Casimir effect
3217:
3211:
3209:
3205:
3204:
3202:
3201:
3196:
3191:
3186:
3181:
3179:Quantum optics
3176:
3171:
3166:
3161:
3156:
3151:
3146:
3141:
3136:
3131:
3126:
3121:
3116:
3111:
3106:
3101:
3100:
3099:
3089:
3084:
3079:
3074:
3073:
3072:
3062:
3057:
3052:
3046:
3044:
3038:
3037:
3035:
3034:
3029:
3024:
3019:
3014:
3009:
3004:
2999:
2994:
2989:
2984:
2978:
2976:
2970:
2969:
2967:
2966:
2961:
2956:
2954:Quantum eraser
2951:
2946:
2941:
2936:
2931:
2926:
2921:
2916:
2910:
2908:
2904:
2903:
2901:
2900:
2895:
2890:
2885:
2880:
2875:
2870:
2869:
2868:
2867:
2866:
2851:
2846:
2841:
2836:
2831:
2825:
2823:
2817:
2816:
2814:
2813:
2808:
2803:
2798:
2793:
2788:
2783:
2778:
2772:
2770:
2766:
2765:
2763:
2762:
2757:
2752:
2747:
2742:
2737:
2732:
2726:
2724:
2720:
2719:
2717:
2716:
2715:
2714:
2709:
2699:
2694:
2689:
2684:
2679:
2674:
2669:
2664:
2659:
2654:
2649:
2644:
2639:
2638:
2637:
2632:
2627:
2622:
2612:
2610:Density matrix
2607:
2602:
2597:
2591:
2589:
2585:
2584:
2582:
2581:
2576:
2571:
2566:
2565:
2564:
2554:
2548:
2546:
2542:
2541:
2536:
2534:
2533:
2526:
2519:
2511:
2505:
2504:
2488:
2483:
2478:
2471:
2470:External links
2468:
2465:
2464:
2394:
2367:Nature Physics
2353:
2342:
2289:
2282:
2254:
2241:10.1086/304147
2200:
2187:
2174:
2162:
2101:
2092:
2063:(3): 336–348.
2047:
2033:
2021:
1996:
1973:
1964:
1893:
1831:
1761:
1704:
1645:
1643:, p. 37f.
1632:
1619:
1618:
1616:
1613:
1612:
1611:
1596:
1585:
1578:
1571:
1566:
1508:
1505:
1504:
1503:
1498:
1491:
1488:
1472:Ma, Zeilinger
1469:
1466:
1444:
1441:
1420:
1417:
1399:
1396:
1382:
1379:
1356:interferometer
1342:
1339:
1334:
1330:
1326:
1318:
1311:
1304:
1289:
1263:
1260:
1232:
1229:
1201:Wheeler's plan
1193:
1192:
1150:
1148:
1141:
1134:
1133:
1084:
1082:
1075:
1061:
1058:
1010:
1007:
938:
935:
901:
900:
898:
897:
890:
883:
875:
872:
871:
867:
866:
861:
856:
851:
846:
841:
836:
831:
826:
821:
816:
811:
806:
801:
796:
791:
786:
781:
776:
771:
766:
761:
756:
751:
746:
741:
736:
731:
726:
721:
716:
711:
706:
701:
696:
691:
686:
681:
676:
671:
666:
661:
656:
651:
646:
641:
635:
634:
631:
630:
627:
626:
623:
622:
617:
612:
607:
605:Density matrix
602:
597:
592:
587:
582:
577:
571:
568:
567:
564:
563:
559:
558:
553:
548:
543:
538:
533:
528:
527:
526:
525:
524:
509:
504:
499:
494:
489:
483:
482:
477:
476:
473:
472:
468:
467:
462:
457:
452:
447:
441:
440:
437:
436:
433:
432:
428:
427:
422:
417:
412:
407:
402:
396:
395:
394:
388:
385:
384:
381:
380:
376:
375:
370:
365:
359:
358:
357:
356:
355:
353:Delayed-choice
348:Quantum eraser
343:
342:
337:
332:
327:
322:
317:
312:
307:
302:
297:
291:
290:
287:
286:
283:
282:
278:
277:
276:
275:
265:
260:
255:
250:
245:
240:
238:Quantum number
235:
230:
225:
220:
215:
210:
204:
203:
200:
199:
196:
195:
191:
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185:
179:
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133:
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109:
102:
99:
93:
90:
87:
83:
76:
73:
69:
64:
61:
50:
49:
43:
42:
26:
24:
14:
13:
10:
9:
6:
4:
3:
2:
3336:
3325:
3322:
3321:
3319:
3304:
3296:
3295:
3292:
3286:
3283:
3281:
3278:
3276:
3273:
3269:
3266:
3265:
3264:
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3258:
3254:
3248:
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3231:
3228:
3226:
3223:
3221:
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3213:
3212:
3210:
3206:
3200:
3197:
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3190:
3187:
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3182:
3180:
3177:
3175:
3172:
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3167:
3165:
3162:
3160:
3157:
3155:
3152:
3150:
3147:
3145:
3142:
3140:
3139:Quantum logic
3137:
3135:
3132:
3130:
3127:
3125:
3122:
3120:
3117:
3115:
3112:
3110:
3107:
3105:
3102:
3098:
3095:
3094:
3093:
3090:
3088:
3085:
3083:
3080:
3078:
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3066:
3063:
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3058:
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3053:
3051:
3048:
3047:
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3043:
3039:
3033:
3030:
3028:
3025:
3023:
3020:
3018:
3015:
3013:
3010:
3008:
3005:
3003:
3000:
2998:
2995:
2993:
2992:Quantum chaos
2990:
2988:
2985:
2983:
2980:
2979:
2977:
2975:
2971:
2965:
2962:
2960:
2959:Stern–Gerlach
2957:
2955:
2952:
2950:
2947:
2945:
2942:
2940:
2937:
2935:
2932:
2930:
2927:
2925:
2922:
2920:
2917:
2915:
2912:
2911:
2909:
2905:
2899:
2896:
2894:
2893:Transactional
2891:
2889:
2886:
2884:
2883:Quantum logic
2881:
2879:
2876:
2874:
2871:
2865:
2862:
2861:
2860:
2857:
2856:
2855:
2852:
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2827:
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2809:
2807:
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2802:
2799:
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2779:
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2774:
2773:
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2758:
2756:
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2748:
2746:
2743:
2741:
2738:
2736:
2733:
2731:
2728:
2727:
2725:
2721:
2713:
2710:
2708:
2705:
2704:
2703:
2702:Wave function
2700:
2698:
2695:
2693:
2690:
2688:
2685:
2683:
2680:
2678:
2677:Superposition
2675:
2673:
2672:Quantum state
2670:
2668:
2665:
2663:
2660:
2658:
2655:
2653:
2650:
2648:
2645:
2643:
2640:
2636:
2633:
2631:
2628:
2626:
2625:Excited state
2623:
2621:
2618:
2617:
2616:
2613:
2611:
2608:
2606:
2603:
2601:
2598:
2596:
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2570:
2567:
2563:
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2559:
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2555:
2553:
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2543:
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2532:
2527:
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2520:
2518:
2513:
2512:
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2501:
2497:
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2479:
2477:
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2372:
2368:
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2354:
2351:
2346:
2343:
2338:
2334:
2330:
2326:
2322:
2318:
2313:
2308:
2305:(3): 033818.
2304:
2300:
2293:
2290:
2285:
2279:
2275:
2271:
2267:
2266:
2258:
2255:
2250:
2246:
2242:
2238:
2234:
2230:
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2216:
2212:
2204:
2201:
2197:
2191:
2188:
2184:
2178:
2175:
2171:
2166:
2163:
2158:
2154:
2150:
2146:
2142:
2138:
2134:
2130:
2125:
2120:
2116:
2112:
2105:
2102:
2096:
2093:
2088:
2084:
2080:
2076:
2071:
2066:
2062:
2058:
2051:
2048:
2044:
2037:
2034:
2030:
2025:
2022:
2010:
2006:
2000:
1997:
1993:
1988:
1983:
1982:New Scientist
1977:
1974:
1968:
1965:
1960:
1956:
1952:
1948:
1944:
1940:
1935:
1930:
1926:
1922:
1917:
1912:
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1904:
1897:
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1773:
1765:
1762:
1757:
1753:
1749:
1745:
1741:
1737:
1732:
1727:
1724:(1): 015005.
1723:
1719:
1715:
1708:
1705:
1700:
1696:
1691:
1686:
1682:
1678:
1673:
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1237:
1230:
1228:
1224:
1216:
1212:
1209:
1199:
1189:
1186:
1178:
1168:
1167:the talk page
1164:
1158:
1156:
1151:This article
1149:
1140:
1139:
1130:
1127:
1119:
1109:
1105:
1101:
1095:
1094:
1090:
1085:This section
1083:
1079:
1074:
1073:
1066:
1059:
1057:
1055:
1054:retroactively
1049:
1045:
1043:
1037:
1033:
1031:
1030:beam splitter
1022:
1018:
1016:
1008:
1006:
1004:
1000:
996:
990:
987:
983:
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790:
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636:
629:
628:
621:
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613:
611:
608:
606:
603:
601:
598:
596:
595:Quantum chaos
593:
591:
588:
586:
583:
581:
578:
576:
573:
572:
566:
565:
557:
554:
552:
551:Transactional
549:
547:
544:
542:
541:Quantum logic
539:
537:
534:
532:
529:
523:
520:
519:
518:
515:
514:
513:
510:
508:
505:
503:
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308:
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303:
301:
298:
296:
293:
292:
285:
284:
274:
271:
270:
269:
268:Wave function
266:
264:
261:
259:
256:
254:
251:
249:
248:Superposition
246:
244:
241:
239:
236:
234:
231:
229:
226:
224:
221:
219:
216:
214:
211:
209:
206:
205:
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162:
156:
155:
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147:
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135:
134:
130:
97:
91:
74:
71:
67:
59:
52:
51:
48:
44:
40:
39:
32:
19:
3022:Quantum mind
2963:
2934:Franck–Hertz
2776:Klein–Gordon
2730:Formulations
2723:Formulations
2652:Interference
2642:Entanglement
2620:Ground state
2615:Energy level
2588:Fundamentals
2552:Introduction
2495:
2412:
2408:
2397:
2370:
2366:
2356:
2345:
2302:
2298:
2292:
2264:
2257:
2217:(1): 75–82.
2214:
2210:
2203:
2195:
2190:
2182:
2177:
2169:
2165:
2114:
2110:
2104:
2095:
2060:
2056:
2050:
2042:
2036:
2028:
2024:
2012:. Retrieved
2008:
1999:
1991:
1986:
1981:
1976:
1967:
1906:
1902:
1896:
1844:
1840:
1834:
1779:
1775:
1764:
1721:
1717:
1707:
1662:
1658:
1648:
1640:
1635:
1627:
1623:
1599:
1588:
1581:
1574:
1519:
1515:
1507:Bibliography
1481:
1479:
1473:
1471:
1461:
1459:
1452:
1448:
1446:
1438:
1434:
1430:
1409:
1405:
1401:
1388:Pockels cell
1384:
1373:
1370:
1361:
1353:
1347:
1344:
1324:
1315:
1308:
1301:
1297:
1293:
1286:
1280:
1275:
1272:
1265:
1255:
1250:
1246:
1242:
1225:
1221:
1204:
1181:
1175:October 2018
1172:
1161:Please help
1152:
1122:
1116:October 2018
1113:
1098:Please help
1086:
1053:
1050:
1046:
1041:
1038:
1034:
1027:
1012:
1002:
998:
994:
991:
969:
963:
958:
942:
940:
937:Introduction
931:
927:
916:proposed by
905:
904:
450:Klein–Gordon
386:Formulations
372:
223:Energy level
218:Entanglement
201:Fundamentals
188:Interference
139:Introduction
3280:EPR paradox
3060:Quantum bus
2929:Double-slit
2907:Experiments
2873:Many-worlds
2811:Schrödinger
2760:Phase space
2750:Schrödinger
2740:Interaction
2697:Uncertainty
2667:Nonlocality
2662:Measurement
2657:Decoherence
2647:Hamiltonian
2045:, p. 486ff.
1482:welcher-weg
1468:Conclusions
839:von Neumann
824:Schrödinger
600:EPR paradox
531:Many-worlds
465:Schrödinger
420:Schrödinger
415:Phase-space
405:Interaction
310:Double-slit
288:Experiments
263:Uncertainty
233:Nonlocality
228:Measurement
213:Decoherence
183:Hamiltonian
3208:Extensions
3042:Technology
2888:Relational
2839:Copenhagen
2735:Heisenberg
2682:Tunnelling
2545:Background
2373:(7): 539.
2070:1602.06100
2014:20 January
1672:1807.03194
1615:References
1157:to readers
834:Sommerfeld
749:Heisenberg
744:Gutzwiller
684:de Broglie
632:Scientists
546:Relational
497:Copenhagen
400:Heisenberg
258:Tunnelling
159:Background
2914:Bell test
2769:Equations
2595:Born rule
2422:1206.6578
2185:, p. 39f.
1929:CiteSeerX
1916:1206.4348
1854:1205.4926
1789:1206.6578
1748:0034-6861
1731:1407.2930
1699:2056-6387
1665:(1): 58.
1608:1407.2930
1087:does not
864:Zeilinger
709:Ehrenfest
438:Equations
115:⟩
112:Ψ
101:^
89:⟩
86:Ψ
63:ℏ
3318:Category
3303:Category
3097:Timeline
2849:Ensemble
2829:Bayesian
2791:Majorana
2707:Collapse
2579:Glossary
2562:Timeline
2500:Archived
2459:23288900
2337:55122015
2198:, p. 41.
2149:17303748
2087:12941256
1959:17859926
1951:23118184
1879:23118183
1826:23288900
1756:34901303
1554:17303748
1490:See also
1390:, and a
1298:particle
999:particle
789:Millikan
714:Einstein
699:Davisson
654:Blackett
639:Aharonov
507:Ensemble
487:Bayesian
392:Overview
273:Collapse
253:Symmetry
144:Glossary
3256:Related
3235:History
2974:Science
2806:Rydberg
2557:History
2496:YouTube
2450:3557028
2427:Bibcode
2375:Bibcode
2317:Bibcode
2249:1249658
2229:Bibcode
2157:6086068
2129:Bibcode
2111:Science
1921:Bibcode
1903:Science
1887:3725159
1859:Bibcode
1841:Science
1817:3557028
1794:Bibcode
1677:Bibcode
1562:6086068
1534:Bibcode
1516:Science
1412:quasars
1153:may be
1108:removed
1093:sources
829:Simmons
819:Rydberg
784:Moseley
764:Kramers
754:Hilbert
739:Glauber
734:Feynman
719:Everett
689:Compton
460:Rydberg
149:History
2949:Popper
2457:
2447:
2335:
2280:
2247:
2155:
2147:
2085:
1957:
1949:
1931:
1885:
1877:
1824:
1814:
1754:
1746:
1697:
1595:) 2004
1560:
1552:
1474:et al.
1462:et al.
1449:et al.
1415:easy.
1208:quasar
1003:before
859:Zeeman
854:Wigner
804:Planck
774:Landau
759:Jordan
410:Matrix
340:Popper
2859:Local
2801:Pauli
2781:Dirac
2417:arXiv
2333:S2CID
2307:arXiv
2245:S2CID
2219:arXiv
2153:S2CID
2119:arXiv
2083:S2CID
2065:arXiv
1955:S2CID
1911:arXiv
1883:S2CID
1849:arXiv
1784:arXiv
1752:S2CID
1726:arXiv
1667:arXiv
1604:arXiv
1558:S2CID
1524:arXiv
1307:. At
814:Raman
799:Pauli
794:Onnes
729:Fermi
704:Debye
694:Dirac
659:Bloch
649:Bethe
517:Local
455:Pauli
445:Dirac
243:State
2786:Weyl
2455:PMID
2278:ISBN
2145:PMID
2016:2014
1947:PMID
1875:PMID
1822:PMID
1744:ISSN
1695:ISSN
1550:PMID
1455:SETI
1294:wave
1091:any
1089:cite
995:wave
849:Wien
844:Weyl
809:Rabi
779:Laue
769:Lamb
724:Fock
679:Bose
674:Born
669:Bohr
664:Bohm
644:Bell
2445:PMC
2435:doi
2413:110
2383:doi
2325:doi
2270:doi
2237:doi
2215:482
2137:doi
2115:315
2075:doi
1939:doi
1907:338
1867:doi
1845:338
1812:PMC
1802:doi
1780:110
1736:doi
1685:doi
1542:doi
1520:315
1374:one
1102:by
949:in
912:in
3320::
2494:.
2453:.
2443:.
2433:.
2425:.
2411:.
2407:.
2381:.
2371:11
2369:.
2365:.
2331:.
2323:.
2315:.
2303:65
2301:.
2276:.
2243:.
2235:.
2227:.
2213:.
2151:.
2143:.
2135:.
2127:.
2113:.
2081:.
2073:.
2061:74
2059:.
2007:.
1953:.
1945:.
1937:.
1927:.
1919:.
1905:.
1881:.
1873:.
1865:.
1857:.
1843:.
1820:.
1810:.
1800:.
1792:.
1778:.
1774:.
1750:.
1742:.
1734:.
1722:88
1720:.
1716:.
1693:.
1683:.
1675:.
1661:.
1657:.
1602:,
1556:.
1548:.
1540:.
1532:.
1518:.
1044:.
2530:e
2523:t
2516:v
2461:.
2437::
2429::
2419::
2391:.
2385::
2377::
2339:.
2327::
2319::
2309::
2286:.
2272::
2251:.
2239::
2231::
2221::
2159:.
2139::
2131::
2121::
2089:.
2077::
2067::
2018:.
1961:.
1941::
1923::
1913::
1889:.
1869::
1861::
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1804::
1796::
1786::
1758:.
1738::
1728::
1701:.
1687::
1679::
1669::
1663:5
1606::
1591:(
1564:.
1544::
1536::
1526::
1335:1
1331:1
1327:1
1319:2
1316:T
1312:1
1309:T
1305:2
1302:T
1290:1
1287:T
1188:)
1182:(
1177:)
1173:(
1169:.
1159:.
1129:)
1123:(
1118:)
1114:(
1110:.
1096:.
941:"
894:e
887:t
880:v
108:|
98:H
92:=
82:|
75:t
72:d
68:d
60:i
20:)
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