Microcausality and Tunneling Times in Relativistic Quantum Field Theory

• URL: http://arxiv.org/abs/2507.09066v2
• Date: Sat, 19 Jul 2025 17:58:48 GMT
• Title: Microcausality and Tunneling Times in Relativistic Quantum Field Theory
• Authors: Mohammed Alkhateeb, Alex Matzkin,
• Abstract summary: We show that microcausality precludes superluminal tunneling dynamics.<n>We illustrate these results with numerical computations for Dirac fermions and Klein-Gordon bosons.
• Score: 0.0
• License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
• 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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