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Rotational Invariance, Phase Relationships and the Quantum Entanglement Illusion

Caroline H Thompson
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Abstract

Another Bell test "loophole" - imperfect rotational invariance - is explored, and novel realist ideas on parametric down-conversion as used in recent "quantum entanglement" experiments are presented. The usual quantum theory of entangled systems assumes we have rotational invariance (RI), so that coincidence rates depend on the difference only between detector settings, not on the absolute values. Bell tests, as such, do not necessarily require RI, but where it fails the presentation of results in the form of coincidence curves can be grossly misleading. Even if the well-known detection loophole were closed, the visibility of such curves would tell us nothing about the degree of entanglement! The problem may be especially relevant to recent experiments using "degenerate type II parametric down-conversion" sources. Logical analysis of the results of many experiments suggests realist explanations involving some new physics. The systems may be more nearly deterministic than quantum theory implies. Whilst this may be to the advantage of those attempting to make use of the so-called "Bell correlations" in computing, encryption, "teleportation" etc., it does mean that the systems obey ordinary, not quantum, logic.

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Caroline H Thompson. 1999-12-16. Rotational Invariance, Phase Relationships and the Quantum Entanglement Illusion. https://arxiv.org/abs/quant-ph/9912082

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