I have had some criticism on a post of mine in another topic. Since I don't want to pollute that thread with my own discussion, and since I am a layman and am really curious about the answer, I'll pose my question here. Consider two polarisation-entangled photons A and B measured by Alice and Bob by means of polarisation filters, which, for this purpose, are at a different spacial angle. Now, if a photon passes Alice's filter, it gets polarisation pol(A). Now B behaves as if it has polarisation -pol(A), and either passes Bob's filter or not. Anyway there is a correlation between the two measurements. However, the same line of reasoning holds for Bob: if a photon passes Bob's filter, it gets polarisation pol(B). Now A behaves as if it has polarisation -pol(B), and either passes Alice's filter or not. Since there is a correlation between the measurements, at some occasions both photon A passes Alice's filter and photon B passes Bob's filter. However, following the above reasoning, Bob's photon has polarisation pol(B) and polarisation -pol(A). Similarly, Alice's photon has polarisation pol(A) and polarisation -pol(B). So we have pol(B)=-pol(A). But to which filter is this polarisation aligned?? Alice's or Bob's? It seems to me a contradiction, unless you pose that the latter photon doesn't take on any defined values as a result of measurement of the first, but instead, for instance, both rather only exhibit a measurement correlation! Moreover, if you take relativity in consideration, you can't tell who causes the the value of the other's photon to get a definite value, for it depends on which reference frame you are in. So who can explain what I am overlooking??