Started by josephpalazzo, May 07, 2014, 11:37:40 AM
Quote from: Casparov on May 07, 2014, 04:29:42 PMWell I am in total agreement with you here. There are however some extra things that both Eraser and Delayed Choice Experiments teach us that the double-slit experiment by itself cannot.A Quantum Eraser for instance shows us that the measuring device alone does not cause collapse unless a conscious observer is able to obtain the which-path information from it.
QuoteIf a measuring device makes a measurement and then the which-path information is made unretrievable (no conscious observer will ever see it), the interference pattern remains as if no measurement had ever taken place. The double-slit alone could not have told us that.
QuoteAlso the Delayed Choice experiment shows us that the wave or particle behavior is not dependent on space-time and violates causality.
Quote from: stromboli on May 07, 2014, 05:09:56 PMYou've only got a lousy PHD, JP. You ain't got a chance.
Quote from: josephpalazzo on May 07, 2014, 04:50:02 PMIt's a speculation that is not borne by the facts. All the measurements are made by detectors. Those results are there whether there is a conscious being reading the results on the detectors or not.The which-path goes to detectors 1 and 2. It matters not if there is a conscious being to observe it. The interference will take place. But we only know this when we look at the oscilloscope that shows the inference pattern. The detector by interacting with the photon to make the measurement has already influenced the result. But in no way, our decision to look at the detector will affect the results. I don't think you know what's involved in the experiment, otherwise you would not make such an implausible statement.
QuoteNo it doesn't. The original paper made that claim. Subsequently that idea was abandoned as it would make no sense. There has never been any experiment that has ever showed that causality is violated. Not to confuse with violations of Bell's theorem, as this is an altogether different thing.
Quote from: Casparov on May 07, 2014, 09:29:43 PMKind sir, are you meaning to tell me that once the signal photon is detected, registered, and scanned at detector D0 according to its position, that no matter what happens beyond this, "the detector by interacting with the photon to make the measurement has already influenced the result," meaning that no matter if we ever know the which-path information or not the wave function will be collapsed every single time because the "unconscious measuring device" made an observation already?Is this your argument? Because you seem to be implying that measuring devices cause the collapse regardless of whether or not they relay information to a conscious observer or not. If you are correct, then the very first measurement that occurs in the experiment should suffice to collapse the wave function every single time, and we should never get an interference pattern.
Quote from: josephpalazzo on May 08, 2014, 10:22:06 AMHere is what you get on the detectors:It doesn't matter if a conscious being looks at the detectors or not, the detectors will show those patterns. To explain the data:The interference occurs at D1 and D2, these are the paths in which we don't know if the photon comes from A or B. This is the same as a double-slit experiment, where we are not trying to know where the photon went through. However for D3, the photon went through the beam splitter BSa making an angle, while for D1, it went right through - follow the diagram carefully. This is the same as adding a detector in a double-slit experiment to figure out which slit the photon went through. By gaining this knowledge with an additional interaction, the interference disappears. Ditto for D4.
Quote from: Casparov on May 08, 2014, 04:18:27 PMI am glad we are having this conversation JosephPalazzo because you are the first person willing to discuss the actual evidence and it's conclusions with me. We disagree but that is fine, let's come to an agreement based on this experiment:
Quote from: Casparov on May 08, 2014, 04:18:27 PMYou say, "It doesn't matter if a conscious being looks at the detectors or not, the detectors will show those patterns." But this is not a testable hypothesis. The only way you can ever know "the detectors will show those patterns" is if a conscious being looks.
Quote from: josephpalazzo on May 08, 2014, 06:30:21 PMDo you believe a tree exists if no one looks at it? Same thing for the patterns on those detectors. If you believe that trees have an existence independent of your perception, so with the patterns as they are registered by the detectors.
QuoteOver the last 30 years there have been quite a few teams of researchers that have investigated DCQE experiments, and all the results give the same results: if there is no knowledge of where the photons have gone through one of the slits, there is interference; if you have knowledge by whatever clever devices you have schemed, there is no interference. And it doesn't matter if the experiment is set up for the interference to happen before or after it arrives at d0. If you find an experiment that says the contrary, please let me know.
QuoteIn this context another novelty of our experiment is particularly important: a new type of detection scheme. In all previous quantum erasers, the observation or not observation of the interference pattern were associated to different experiments, or at least to different photoelec- tric detectors. Therefore even though the physics behind the erasure has been exploited, the implementation of the random delayed choice can still be improved. In our real- ization both the erasing choice and the reading choice are analyzed by a single detector. This characteristic stresses the interpretative difficulties of the quantum eraser. In fact in our experiment the particle-like and wave-like be- havior of the photon are recorded randomly and simul- taneously by the same pair of joint measurement devices in only one measurement process.
QuoteWe have presented a quantum eraser that uses a Young double slit to create interference. The quarter-wave plates inour experiment served as the which-path markers to destroy interference. We recovered interference using the entangle- ment of photons s and p. Our quantum eraser is very similar to the that of Scully, Englert, and Walther. We have shown that interference can be destroyed, by marking the path of the interfering photon, and recovered, by making an appropriate measurement on the other entangled photon. We have also investigated this experiment under the conditions of delayed erasure, in which the interfering photon s is de- tected before photon p. In as much as our experiment did not allow for the observer to choose the polarization angle in the time period after photon s was detected and before detectionof p, our results show that a collapse of the wave function due to detection of photon s does not prohibit one from ob- serving the expected results. Our experimental data agree with the proposal of Scully, Englert, and Walther that quan- tum erasure can be performed after the interfering particle has been detected.
Quote from: Casparov on May 08, 2014, 07:57:34 PMThis is not a trivial question. Einstein asked Bohr, "Do you really believe the moon is not there when nobody looks?" To which Bohr replied, â€œCan you prove to me the contrary?â€ It is a serious question to ask.
QuoteRealism is the assumption that [...]
Quote from: Casparov on May 08, 2014, 07:57:34 PMThis is not a trivial question. Einstein asked Bohr, "Do you really believe the moon is not there when nobody looks?" To which Bohr replied, â€œCan you prove to me the contrary?â€ It is a serious question to ask.Realism is the assumption that perceived objects have an existence independent of perception, and I believe that what quantum mechanics is showing us is that there is no need for that assumption. Unless someone can "prove to me the contrary?"
QuoteYes but the claim I am refuting is the one which states, "the measuring devices themselves are the cause of the wave function collapse." These experiments disprove this claim outright. If unconscious measuring devices were the sole cause of the "observer effect" of collapsing wave functions, then whether or not the recorded which-path information is at a later time erased or not should have no effect. The wave function should stay collapsed because the unconscious measuring device made the "observation." Do you disagree?
QuoteIn all these experiments, unconscious detecters can "measure" or "observe" the which-path information, but this does not cause collapse if that which-path information never makes it to a conscious observer. Thus, proving that unconscious detecters and measuring devices themselves are not the cause of wave function collapse, and not the cause of the "observer effect." Otherwise, no matter what happens after the measurement from an unconscious detector, the wave function would stay collapsed.
Quote from: josephpalazzo on May 09, 2014, 07:11:38 AMSorry to disagree, but as I have already stated there is only one conclusion from all DCQE experiments: if you know the which-path there is no interference; if you do not know it, there will be interference. Any contrary result would be an exception to the Heisenberg Uncertainty Principle, and that would be so big, so huge, it would have hit the headlines of all the major papers and that person would be in line for the Nobel.
QuoteShimon Malin Phd. Professor Emeritus of Physics at Colgate University"Suppose a measurement of an electron's spin component along some direction is being measured. The result can either be "up" or "down". The result of the measurement is automatically communicated to a printer that can either print "up" or "down". If human consciousness is what causes the collapse to the observed state, then the collapse would only occur when someone read the printout, and not before. Now suppose that the printer has just enough ink to print "up", and not enough ink to print "down". Furthermore, if the printer runs out of ink, a bell sounds in a secretary's office. If the secretary hears the bell, a collapse to "down" has clearly occurred before the bell sounded. If the secretary does not hear the bell, a collapse to "up" must have occurred--and no human interaction was necessary at all."