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arXiv · 1509.01475

Mid- and far-field deviations from causality in spontaneous light emission by atomic Hydrogen

Vincent Debierre·Thomas Durt
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Abstract

We investigate, in the case of the $2\mathrm{p}-1\mathrm{s}$ transition in atomic Hydrogen, the behaviour of the spontaneously emitted electromagnetic field in spacetime. We focus on Glauber's wave function for the emitted photon, a quantity which we find is nonzero outside the lightcone at all times after the start of the emission. We identify the uncertainty on the position of the decaying electron as a source of departure from causality in the naive sense of the term. We carry out a detailed study of the emitted electric field in the mid- and far-field regions, through analytical and numerical computations as well as asymptotic arguments.

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Vincent Debierre, Thomas Durt. 2015-09-04. Mid- and far-field deviations from causality in spontaneous light emission by atomic Hydrogen. https://arxiv.org/abs/1509.01475

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