lugita15
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To me the answer is clear: both rates are calculated from the individual detection results, so the only relevant parameters are those that determine the individual detection results.ThomasT said:I'm just wondering how the rate of individual detection and the rate of coincidental detection can be attributed to the same underlying parameter.
Yes, I also feel that much of our disagreement may be due to semantics.Yes, I agree. The language surrounding all this can get confusing. But I know what you're saying.
I mean, suppose we have sent an entangled pair of photons through the polarizers, and e.g. we may get 1 on the first detector and 0 on the second detector. Then given these individual detection results, the answer to the question "Was there a mismatch?" is completely determined. So mismatches cannot be depend on any parameter that the individual detection results don't already depend on.I'm not sure what you mean by this.lugita15 said:And that if the individual detection results are the same, then the mismatches are the same?
I think this is more semantics. To my mind, the data sets are just composed of the individual data entries, i.e. the individual detection results. So how can the data set as a whole be determined by anything other than what determines each individual entry?I don't disagree with it. But the individual detection sequences, considered separately, are different data than the sequences, appropriately combined, considered together. The two different data sets are correlated with different measurement parameters.
I don't get your point here. To me, it seems so obvious that teh angular difference is nothing more and nothing less than the difference of the settings of the settings of the two polarizers, so there's nothing special about it.The setting of polarizer a or b is not the same observational context as the angular difference between a and b.
I don't know whether I can, but I can try to explain my notation and then you can ask me what you don't get. Starting from the top, QM predicts that for an entangled pair of photons, you always get identical detection results at identical polarizer settings. From this, the local determinist concludes that both photons are using the same function P(θ) to determine whether to go through the polarizer or not. P has only two values it can have, 0 and 1. If one of the photons encounters a polarizer oriented at a given angle, it plugs the angle into the function P and gets either a 0 or 1 as the answer. If 0, then it doesn't go through the polarizer, and if 1 then it does. Are you clear up to there?Your notation is a bit confusing for me. Say in words what you mean by the above notations.
So now the following experiment is done. Polarizer 1 is turned to the angle θ1, Polarizer 2 is turned to θ2, and then we send a trillion entangled pairs of photons to the two polarizers. Each experimeter writes down a list of yes or no answers as to whether each photon goes through the polarizer or not. Then we calculate R(θ1,θ2), which is the percentage of pairs whose individual detection results had a mismatch. Another way of putting this is that R(θ1,θ2) is the observed probability that a randomly selected entangled pair will have a mismatch between individual detection results. Are you clear on that?
Now remember, the individual detection results for a given pair are determined by the function P. So if the pair has a mismatch when one polarizer is oriented at θ1 and one polarizer is oriented at θ2, what that means is that P(θ1)≠P(θ2), meaning the P function for that pair is telling you to do different things at the angle θ1 versus the angle θ2. Now remember, R(θ1,θ2) is the probability that a randomly selected pair will have a mismatch when the polarizers are set at θ1 and θ2. In other words, R(θ1,θ2) is the probability that a randomly selected pair will have a P function which gives contradictory messages at θ1 and θ2, or to put it more simply R(θ1,θ2) is the probability that a randomly selected pair has a P function such that P(θ1)≠P(θ2). Are you clear on that? If you are, then step 5 follows pretty directly. (You see me frequently writing R(θ) instead of R(θ1,θ2), because R(θ1+C,θ2+C)=R(θ1,θ2) for all C, so in particular R(θ1-θ2,0)=R(θ1,θ2), so we can write R(θ1,θ2)=R(θ,0)=R(θ), where θ=θ1-θ2; I hope that's not too confusing.)
But all these data sequences are composed of the individual detection results, so the only relevant parameter are whatever determines these results. I'm sorry for repeating myself, but I feel like we're communicating on different wavelengths.Ultimately, yes. But the organization of the data, how it's parsed or matched, and what it's correlated with is determined by the experimental design. Individual data sequences composed of 0's and 1's aren't the same as combined data sequences composed of (1,1)'s, (0,0)'s, (1,0)'s, and (0,1)'s.