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arXiv · 1709.07052

A Completely Top-Down Hierarchical Structure in Quantum Mechanics

Yakir Aharonov·Eliahu Cohen·Jeff Tollaksen
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Abstract

Can a large system be fully characterized using its subsystems via inductive reasoning? Is it possible to completely reduce the behavior of a complex system to the behavior of its simplest "atoms"? In the following paper we answer these questions on the negative for a specific class of systems and measurements. We begin with simple two-particle example, where strong correlations arise between two apparently empty boxes. This leads to new surprising effects within atomic and electromagnetic systems. A general construction based on pre- and post-selected ensembles is then suggested, where the N-body correlation can be genuinely perceived as a global property, as long as one is limited to preforming a small set of measurements which we term "strictly local". We conclude that within time-symmetric quantum mechanics and under certain boundary conditions, high-order correlations can determine low-order ones, but not vice versa. Moreover, the latter seem to provide no information at all regarding the former. This supports a top-down structure in many-body quantum mechanics.

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Yakir Aharonov, Eliahu Cohen, Jeff Tollaksen. 2017-09-20. A Completely Top-Down Hierarchical Structure in Quantum Mechanics. https://doi.org/10.1073/pnas.1807554115

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