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Video# Conditions for Lorentz-invariant superluminal information transfer without signaling

Gerhard Grössing Vienna University of TechnologyWe understand emergent quantum mechanics in the sense that quantum mechanics describes processes of physical emergence relating an assumed sub-quantum physics to macroscopic boundary conditions. The latter can be shown to entail top-down causation, in addition to usual bottom-up scenarios. With this example it is demonstrated that definitions of “realism“ in the literature are simply too restrictive.

A prevailing manner to define realism in quantum mechanics is in terms of pre-determination independent of the measurement. With our counter-example, which actually is ubiquitous in emergent, or self-organizing, systems, we argue for realism without pre-determination. We refer to earlier results of our group showing how the guiding equation of the deBroglie-Bohm interpretation can be derived from a theory with classical ingredients only.[1-3] Essentially, this corresponds to a “quantum mechanics without wave functions“ in ordinary 3-space, albeit with nonlocal correlations.

This, then, leads to the central question of how to deal with the nonlocality problem in a relativistic setting. We here show that a basic argument discussing the allegedly paradox time ordering of events in EPR-type two-particle experiments falls short of taking into account the contextuality of the experimental setup. Consequently, we then discuss under which circumstances (i.e. physical premises) superluminal information transfer (but not signaling [4]) may be compatible with a Lorentz-invariant theory.

Finally, we argue that the impossibility of superluminal signaling – despite the presence of superluminal information transfer – is not the result of some sort of conspiracy (á la “Nature likes to hide”), but the consequence of the impossibility of infinite precision of a state’s preparation, or of the no-cloning theorem, respectively.

[1] G. Grössing, “The Vacuum Fluctuation Theorem: Exact Schrödinger Equation via Nonequilibrium Thermodynamics”, Phys. Lett. A 372 (2008) 4556-4563. quant-ph/arXiv:0711.495

[2] G. Grössing, S. Fussy, J. Mesa Pascasio, and H. Schwabl, “Extreme beam attenuation in double-slit experiments: Quantum and subquantum scenarios”, Ann. Phys. 353 (2015) 271–281. arXiv:1406.1346 [quant-ph]

[3] G. Grössing, S. Fussy, J. Mesa Pascasio, and H. Schwabl, “Implications of a deeper level explanation of the deBroglie-Bohm version of quantum mechanics”. Quantum Stud.: Math. Found. 2, 1 (2015), 133-140

[4] J. Walleczek and G. Grössing, “Nonlocal quantum information transfer without superluminal signalling and communication”, arXiv:1501.07177v2 [quant-ph]