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arXiv · 2208.09742

Subluminality of relativistic quantum tunneling

Lorenzo Gavassino·Marcelo M. Disconzi
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Abstract

We prove that the classical Dirac equation in the presence of an external (nondynamical) electromagnetic field is a relativistically causal theory. As a corollary, we show that it is impossible to use quantum tunneling to transmit particles or information faster than light. When an electron tunnels through a barrier, it is bound to remain within its future light cone. In conclusion, the relativistic quantum tunneling (if modeled using the Dirac equation) is an entirely subluminal process, and it is not instantaneous.

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Lorenzo Gavassino, Marcelo M. Disconzi. 2023-03-13. Subluminality of relativistic quantum tunneling. https://doi.org/10.1103/physreva.107.032209

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