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arXiv · 2004.09723

Classical perspectives on the Newton--Wigner position observable

Philip K. Schwartz·Domenico Giulini
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Abstract

This paper deals with the Newton--Wigner position observable for Poincaré-invariant classical systems. We prove an existence and uniqueness theorem for elementary systems that parallels the well-known Newton--Wigner theorem in the quantum context. We also discuss and justify the geometric interpretation of the Newton--Wigner position as `centre of spin', already proposed by Fleming in 1965 again in the quantum context.

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Philip K. Schwartz, Domenico Giulini. 2020-09-09. Classical perspectives on the Newton--Wigner position observable. https://doi.org/10.1142/s0219887820501765

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