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arXiv · 1709.10085

Back-reaction on background fields: a coherent state approach

Anton Ilderton·Daniel Seipt
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Abstract

There are many situations in which a strong electromagnetic field may be approximated as a fixed background. Going beyond this approximation, i.e. accounting for the back-reaction of quantum process on the field, is however challenging. Here we develop an approach to this problem which is a straightforward extension of background field methods. The approach follows from the observation that scattering in an on-shell background is equivalent to scattering between coherent states; we show that by deforming these states one can model back-reaction. Focussing on intense laser-matter interactions, we provide examples which model beam depletion and, furthermore, introduce an extremisation principle with which to determine the level of depletion in a given scattering process.

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Anton Ilderton, Daniel Seipt. 2017-09-28. Back-reaction on background fields: a coherent state approach. https://doi.org/10.1103/physrevd.97.016007

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