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arXiv · 2507.09066

Microcausality and Tunneling Times in Relativistic Quantum Field Theory

Mohammed Alkhateeb·Alex Matzkin
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Abstract

We show, in the framework of a space-time resolved relativistic quantum field theory approach to tunneling, that microcausality precludes superluminal tunneling dynamics. More specifically in this work dealing with Dirac and Klein-Gordon fields, we first prove that microcausality holds for such fields in the presence of a background potential. We then use this result to show that an intervention performed on a localized region of an initial wave packet subsequently scattering on a potential barrier does not result in any effect outside the light cone emanating from that region. We illustrate these results with numerical computations for Dirac fermions and Klein-Gordon bosons.

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Mohammed Alkhateeb, Alex Matzkin. 2025-07-11. Microcausality and Tunneling Times in Relativistic Quantum Field Theory. https://doi.org/10.1103/4sh5-d838

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