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arXiv · 1911.06518

On quantization in background scalar fields

E. T. Akhmedov·E. N. Lanina·D. A. Trunin
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Abstract

We consider (0+1) and (1+1) dimensional Yukawa theory in various scalar field backgrounds, which are solving classical equations of motion: $\ddotϕ_{cl} = 0$ or $\Box ϕ_{cl} = 0$, correspondingly. The (0+1)--dimensional theory we solve exactly. In (1+1)--dimensions we consider background fields of the form $ϕ_{cl} = E\, t$ and $ϕ_{cl} = E\, x$, which are inspired by the constant electric field. Here $E$ is a constant. We study the backreaction problem by various methods, including the dynamics of a coherent state. We also calculate loop corrections to the correlation functions in the theory using the Schwinger--Keldysh diagrammatic technique.

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E. T. Akhmedov, E. N. Lanina, D. A. Trunin. 2020-02-23. On quantization in background scalar fields. https://doi.org/10.1103/physrevd.101.025005

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