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Cherenkov radiation and superluminal particles

Daniel Rohrlich·Yakir Aharonov
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Abstract

Any charged particle moving faster than light through a medium emits Cherenkov radiation. We show that charged particles moving faster than light through the v a c u u m emit Cherenkov radiation. How can a particle move faster than light? The w e a k speed of a charged particle can exceed the speed of light. By definition, the weak velocity is / where v is the velocity operator and |a> and |b> are, respectively, the states of a particle before and after a velocity measurement. We discuss the consistency of weak values and show that superluminal weak speed is consistent with relativistic causality.

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Daniel Rohrlich, Yakir Aharonov. 2002-08-05. Cherenkov radiation and superluminal particles. https://doi.org/10.1103/physreva.66.042102

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