Schmelzer wrote:minkwe wrote:Since we are getting silly distractions instead of counterarguments, let me yet again summarize my arguments:
It is, hear, a silly distraction if I ask minkwe if he really believes that QM predicts 50% A=B and 50% A=-B if Alice and Bob measure in the same direction of the same particle pair but at different times, where QM predicts 100% A=-B.minkwe wrote:1. There is no "locality assumption" in Bell's derivation of his inequalities. None whatsoever, despite repeated noises about "locality".
Nonsense.Bell wrote:Now we make the hypothesis 2, and it seems one at least worth considering, that if the two measurements are made at places remote from
one another the orientation of one magnet does not influence the result obtained with the other.
is a locality assumption.
Feel free to make your own proofs of Bell's inequalities on whatever assumptions you like, but Bell has made a locality assumption, and this is a trivial fact.minkwe wrote:Therefore, any insistence that locality is required is simply poppycock, and a waste of time.
In Bell's proof it is assumed, which is all what matters.2. The counterfactual definiteness assumption invoked by Bell applies to QM as well. Bell himself uses it on page 1 to make a QM argument.
Given that you have completely nonsensical ideas about what QM predicts, this is impossible to discuss with you.
Of course, if the wave function is in an eigenstate of some operator, the result of measuring this particular operator is predetermined, and, therefore, counterfactually definite - it will give the eigenvalue of this eigenstate. But this is all what is predetermined in QM.
Bell, of course, uses this fact, in particular he uses the fact that after the measurement of Bob the particle of Alice will be in an eigenstate of the spin operator in the direction measured by Bob with eigenvalue -B.Bell's 2nd and 3rd sentence in paragraph 2 of page 1, applies CFD to quantum mechanics as follows: If Alice measures along "a" and obtained +1, then if Bob were to measure the sister particle along "a" he must obtain -1. Clearly, Bell believes and QM states that the measurement that was not performed has a single definite value. In fact, CFD applies to any theory that makes predictions. Any suggestion otherwise reflects lack of thinking ability, as it can easily shown that a prediction for an experiment which ends up not being done, is counterfactually definite. No theory is immune to this, including QM.
You seem unable or unwlling to make the trivial distinction between theories which assume counterfactual definiteness for all predictions from those who do it only in very special cases. QM has counterfactual definiteness only for measurements of very particular states - the eigenstates of the operator which describes the measurement.
For all other measurements, it makes nontrivial predictions - about probabilities. Probabilistic predictions do not need any counterfactual definiteness assumption, but are physical predictions, thus, your claim that CFD applies to every theory making predictions is nonsense.3. Bell's inequality relates one actual measurement, to two counterfactual measurements which could have been done but weren't.
No, it relates averages.
Bell uses the counterfactual definiteness in the proof of the theorem, which is unproblematic because it has been derived based on the locality assumption and the EPR argument. It is not part of the inequalities.
You obviously don't understand that it is part of the proof that the P(a,b) will be the same in different experiments, because of the law of large numbers. This allows you to measure P(a,b), P(b,c) and P(a,c) in three different experiments.4. Bell's inequality can not be derived if we do not assume counterfactual results, but instead use actual independent measurements .
Of course it cannot be derived from measurement results alone. A triviality without value.5. Even if it were possible to measure the same pair of particles at all three pairs of settings (which is impossible to do), Bell's derivation requires that all the measurements are done at the same time.
Simply wrong. Learn elementary QM.
It looks like you have not understood why in some experiments one has to be careful to measure time. This is simply because these experiments use a lot of different pairs following each other in rather short time intervals, so that time measurements are used to clarify if the two measurements made by Alice and Bob are really measurements of the same pair.Imagine the two particles tumbling in concert as they move apart, at a given frequency, such that their vectors maintain a fixed relationship to each other.
Imagine pink little fairies are dancing in concert as they move apart. But, then, please wake up and care about the actual predictions of QM.
minkwe has yet refused to answer if he really believes that QM predicts 50% A=B and 50% A=-B if Alice and Bob measure in the same direction of the same particle pair but at different times, where QM predicts 100% A=-B.
We are still waiting for you to show us exactly how QM violates the Bell inequality. Otherwise, none of what you say above matters.
