by gill1109 » Sun Jun 01, 2014 11:35 am
Joy Christian wrote:Therefore it is all the more important that my proposed experiment is realized as soon as possible, even if it turns out to prove me totally wrong. It is a wonderful opportunity---and I claim the only opportunity---where we can test the viability of local realism decisively. It is the only experiment that can actually refute local realism. It is the only experiment in which all of the actual and counterfactual outcomes would exist in a data set, for all eternity, without zero outcomes.
Unfortunately the experiment is certain to fail:
Joy Christian wrote:gill1109 wrote:Equation (16) is E(a, b) = 1/N sum_{j = 1}^N {sign (λj · a)} {sign(−λj · b)}
So: are a, b and λj unit vectors in R^3 ?
Is "." the scalar dot product?
Is "sign" the usual sign function?
Is everything else ordinary arithmetic?
Are a, b and λj unit vectors in R^3 ?
Yes.
Is "." the scalar dot product?
Yes.
Is "sign" the usual sign function?
Yes.
Is everything else ordinary arithmetic?
Yes.
gill1109 wrote:No ambiguities.
Suppose the experiment has delivered us the data sets u_1, ... u_N and v_1, ..., v_N.
Define
A = A(j) = sign(a . u_j),
A' = A'(j) = sign(a' . u_j),
B = B(j) = sign(b . v_j),
B' = B'(j) = sign(b'. v_j)
For each j, A B + A B' + A'B - A'B' = +/- 2.
Therefore averaging over j = 1 ... N
E(a, b) + E(a, b') + E(a', b) - E(a', b') lies between -2 and +2
Thus there is no way that three of the correlations will be within +/- 0.2 of 0.7071 and one within +/- 0.2 of - 0.7071.
Because every smart experimentalist can see that the experiment cannot succeed, no smart experimentalist will ever perform the experiment, and therefore Joy Christian and his followers can believe in his theory for ever.
Everybody gets to live happily ever after. It's indeed a cargo cult, as Florin Moldoveanu pointed out.
It's a bit like the following. Someone has a wonderful physical theory which depends on the square root of 2 being a rational number. His theory will be proven wrong by experiment, if the experiment would generate two positive integers p and q such that p^2 = 2 q^2. The theorist writes paper after paper and urges experimentalists to do his experiment. Let Nature be the arbiter! However, every clever experimentalist can very well understand Euclid's proof that no postive integers p and q exist such that p^2 = 2 q^2. The theorist remains a misunderstood genius to his death; his experiment (which could prove him right) is never performed; on the other hand, performing the experiment however many times would always result in failure so there is not much point in doing it.
Everybody gets to live happily ever after.
Incidentally, I know several renowned experimental physicists who don't believe Euclid was right. How can you prove that sqrt 2 is irrational, by assuming that it is not irrational? That's obviously pure stupidity.
"Impossibility proofs" are difficult to understand for practical minded people.
I'm reminded of an episode in the trials of alleged serial killer nurse Lucia de Berk. A probabilist tried to explain that a certain statistical calculation was wrong by performing a thought experiment in which he increased the numbers of wards in which the nurse had worked from 3 to some indefinitely large number. The judges cut him short. "We are not here to do thought experiments, we are here to ascertain the facts". Lucia got a life sentence plus thereafter indefinite detention in psychiatric hospital for 7 murders and 3 attempted murders ... none of which had actually happened. (Unless you count the usual life-shortening mistakes of medical specialists "murders". Every year in the Netherlands there are 2000 hospital deaths caused by avoidable medical errors. Almost none of them are admitted to have been caused by medical errors. Dutch medical specialists don't have to pay insurance against being sued for malpractice because they can't be sued for malpractice! Oh well, that lowers the cost of medical care.).
Einstein performed a thought experiment in the EPR paper: he imagined that instead of Alice measuring her particle's momentum, she had instead measured its position. What would Bob then have seen, if he had measured either position or momentum of his particle?
Einstein used the predictions of quantum theory, and locality, in order to infer realism, and from this, to infer the incompleteness of quantum mechanics. So was Einstein just as mistaken as John Bell? What colossal stupidity, to imagine the outcomes of different measurements from those which actually get performed (if any). We must resolutely forbid thought experiments. The only thing allowed in physics is (a) actual experiments, (b) simulation models of actual experiments.
[quote="Joy Christian"]
Therefore it is all the more important that my proposed experiment is realized as soon as possible, even if it turns out to prove me totally wrong. It is a wonderful opportunity---and I claim the only opportunity---where we can test the viability of local realism decisively. It is the only experiment that can actually refute local realism. It is the only experiment in which all of the actual and counterfactual outcomes would exist in a data set, for all eternity, without zero outcomes.
[/quote]
Unfortunately the experiment is certain to fail:
[quote="Joy Christian"][quote="gill1109"]
Equation (16) is E(a, b) = 1/N sum_{j = 1}^N {sign (λj · a)} {sign(−λj · b)}
So: are a, b and λj unit vectors in R^3 ?
Is "." the scalar dot product?
Is "sign" the usual sign function?
Is everything else ordinary arithmetic?
[/quote]
[list]Are a, b and λj unit vectors in R^3 ?[/list]
Yes.
[list]Is "." the scalar dot product?[/list]
Yes.
[list]Is "sign" the usual sign function?[/list]
Yes.
[list]Is everything else ordinary arithmetic?[/list]
Yes.
[/quote]
[quote="gill1109"]No ambiguities.
Suppose the experiment has delivered us the data sets u_1, ... u_N and v_1, ..., v_N.
Define
A = A(j) = sign(a . u_j),
A' = A'(j) = sign(a' . u_j),
B = B(j) = sign(b . v_j),
B' = B'(j) = sign(b'. v_j)
For each j, A B + A B' + A'B - A'B' = +/- 2.
Therefore averaging over j = 1 ... N
E(a, b) + E(a, b') + E(a', b) - E(a', b') lies between -2 and +2[/quote]
Thus there is no way that three of the correlations will be within +/- 0.2 of 0.7071 and one within +/- 0.2 of - 0.7071.
Because every smart experimentalist can see that the experiment cannot succeed, no smart experimentalist will ever perform the experiment, and therefore Joy Christian and his followers can believe in his theory for ever.
Everybody gets to live happily ever after. It's indeed a cargo cult, as Florin Moldoveanu pointed out.
It's a bit like the following. Someone has a wonderful physical theory which depends on the square root of 2 being a rational number. His theory will be proven wrong by experiment, if the experiment would generate two positive integers p and q such that p^2 = 2 q^2. The theorist writes paper after paper and urges experimentalists to do his experiment. Let Nature be the arbiter! However, every clever experimentalist can very well understand Euclid's proof that no postive integers p and q exist such that p^2 = 2 q^2. The theorist remains a misunderstood genius to his death; his experiment (which could prove him right) is never performed; on the other hand, performing the experiment however many times would always result in failure so there is not much point in doing it.
Everybody gets to live happily ever after.
Incidentally, I know several renowned experimental physicists who don't believe Euclid was right. How can you prove that sqrt 2 is irrational, by assuming that it is not irrational? That's obviously pure stupidity.
"Impossibility proofs" are difficult to understand for practical minded people.
I'm reminded of an episode in the trials of alleged serial killer nurse Lucia de Berk. A probabilist tried to explain that a certain statistical calculation was wrong by performing a thought experiment in which he increased the numbers of wards in which the nurse had worked from 3 to some indefinitely large number. The judges cut him short. "We are not here to do thought experiments, we are here to ascertain the facts". Lucia got a life sentence plus thereafter indefinite detention in psychiatric hospital for 7 murders and 3 attempted murders ... none of which had actually happened. (Unless you count the usual life-shortening mistakes of medical specialists "murders". Every year in the Netherlands there are 2000 hospital deaths caused by avoidable medical errors. Almost none of them are admitted to have been caused by medical errors. Dutch medical specialists don't have to pay insurance against being sued for malpractice because they can't be sued for malpractice! Oh well, that lowers the cost of medical care.).
Einstein performed a thought experiment in the EPR paper: he imagined that instead of Alice measuring her particle's momentum, she had instead measured its position. What would Bob then have seen, if he had measured either position or momentum of his particle?
Einstein used the predictions of quantum theory, and locality, in order to infer realism, and from this, to infer the incompleteness of quantum mechanics. So was Einstein just as mistaken as John Bell? What colossal stupidity, to imagine the outcomes of different measurements from those which actually get performed (if any). We must resolutely forbid thought experiments. The only thing allowed in physics is (a) actual experiments, (b) simulation models of actual experiments.
