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Quantum nonlocality and quantum dynamics

S. Gheorghiu-Svirschevski
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Abstract

We argue that usual quantum statics and the dynamical equivalence of mixed quantum states to {\it probabilistic mixtures}suffice to guarantee a linear evolution law, which necessarily complies with the no-signaling condition. Alternatively, there are nonlinear dynamical extensions that treat mixed states as {\it elementary mixtures} and evolve {\it every}pure state linearly and unitarily. But if all {\it entangled} pure states evolve linearly, then elementary mixtures cannot evolve nonlinearly without challenging quantum locality. Conversely, any such extension that is relativistically well behaved demands a nonlinear evolution [decoherence] of pure entangled states. Wherefrom follows that the linear evolution of entangled pure states provides an unequivocal signature of linear quantum dynamics.

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S. Gheorghiu-Svirschevski. 2002-07-08. Quantum nonlocality and quantum dynamics. https://arxiv.org/abs/quant-ph/0203153

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