AJセミナー「To be or not to be ― qubits don't think, therefore we don't know!」

概要：Long time ago, in a distant minuscule scale... Quantum wars! The republic of researchers fought over the structure of the small world, throwing probabilities, hidden variables, and laws for their senate to discuss. The discord spread around facts, counter examples, contradictions, and inconsistencies, with various sages questioning whether signals could spookily travel faster than light [1], others saying that such signals could not be, but the theory still could [2,3]. The underlying nonlocal structure started to be accepted as factual, when overall dismay increased with a new questioning: why not more nonlocality [4]? As the republic of letters stalled new doubts, we come forth this discussion with an old but renewed argument: the indifference of minuscule packets, including information packets, a.k.a. indistinguishability(*). We try to restore peace and harmony to the microscopic world by showing that indistinguishability limits the nonlocality achievable by quantum means. Therefore, if we require indistinguishability, the correlation bounds known to the masters [5] shall not be violated by any black box.

Reference:

[1] Einstein, A., Podolsky, B. & Rosen, N.: Can quantum mechanical description of physical reality be considered complete? Phys. Rev. 47, 777-780 (1935). https://journals.aps.org/pr/abstract/10.1103/PhysRev.47.777

[2] Bell, J. S.: On the Einstein Podolsky Rosen paradox. Phys. 1, 195-290 (1964). https://cds.cern.ch/record/111654/files/vol1p195-200_001.pdf

[3] Clauser, J. F., Horne, M. A., Shimony, A. & Holt, R. A.: Proposed experiment to test local hidden variable theories. Phys. Rev. Lett. 23, 880-884 (1969). https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.23.880

[4] Popescu, S. & Rohrlich, D.: Quantum nonlocality as an axiom. Foundations Phys. 24, 379-385 (1994). https://link.springer.com/article/10.1007/BF02058098

[5] Cirel'son, B. S.: Quantum generalizations of Bell's inequality. Lett. Math. Phys. 4, 93-100 (1980). https://link.springer.com/article/10.1007/BF00417500 [6] Amorim, C. S.: Indistinguishability as nonlocality constraint. arXiv:1610.03605. https://arxiv.org/abs/1610.03605