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arXiv · 2009.13068

On a proper-time approach to localization

E. R. F. Taillebois·A. T. Avelar
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Abstract

The causality issues concerning Hegerfeldt's paradox and the localization of relativistic quantum systems are addressed through a proper-time formalism of single-particle operators. The proposed description does not depend on classical parameters connected to an external observer and results in a single-particle formalism in which localization is described by explicitly covariant four-vector operators associated with POVM measurements parametrized by the system's proper-time. As a consequence, it is shown that physically acceptable states are necessarily associated with the existence of a temporal uncertainty and their proper-time evolution is not subject to the causality violation predicted by Hegerfeldt.

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E. R. F. Taillebois, A. T. Avelar. 2020-09-24. On a proper-time approach to localization. https://arxiv.org/abs/2009.13068

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