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arXiv · 1704.00482

One-particle reducible contribution to the one-loop scalar propagator in a constant field

James P. Edwards·Christian Schubert
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Abstract

Recently, Gies and Karbstein showed that the two-loop Euler-Heisenberg Lagrangian receives a finite one-particle reducible contribution in addition to the well-known one-particle irreducible one. Here, we demonstrate that a similar contribution exists for the propagator in a constant field already at the one-loop level, and we calculate this contribution for the scalar QED case. We also present an independent derivation of the Gies-Karbstein result using the worldline formalism, treating the scalar and spinor QED cases in a unified manner.

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James P. Edwards, Christian Schubert. 2017-04-14. One-particle reducible contribution to the one-loop scalar propagator in a constant field. https://doi.org/10.1016/j.nuclphysb.2017.08.002

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