DrChinese
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greswd said:what's a backward-in-time influence?
No one really knows. However, just as it is possible to demonstrate "nonlocality" with entanglement (and this is a prediction of QM), it is also possible to demonstrate "non-temporality" (I made up this word) or "non-causality". And this is also predicted by QM. For instance:
1. It is possible to entangle photons AFTER they have been detected.
2. It is possible to entangle photons that have never co-existed.
3. It is possible to entangle photons that have never shared a common light cone.
Yet in all of these cases, there are world lines (respecting c) connecting the photons which go both forward and backward in time. And ALL entanglement - even a so-called "non-local" demonstration - shares this strange attribute. I do not know what to make of it any more than anyone else, but there are interpretations of QM that feature elements of time symmetry.
I can provide references if that will help.