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arXiv · 2102.03407

Energy-momentum tensor and effective Lagrangian of scalar QED with a nonminimal coupling in 2D de Sitter spacetime

Marzieh Akbari Ahmadmahmoudi·Ehsan Bavarsad
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Abstract

We have studied the induced one-loop energy-momentum tensor of a massive complex scalar field within the framework of nonperturbative quantum electrodynamics (QED) with a uniform electric field background on the Poincar\'e patch of the two-dimensional de Sitter spacetime ($\mathrm{dS_{2}}$). We also consider a direct coupling the scalar field to the Ricci scalar curvature which is parameterized by an arbitrary dimensionless nonminimal coupling constant. We evaluate the trace anomaly of the induced energy-momentum tensor. We show that our results for the induced energy-momentum tensor in the zero electric field case, and the trace anomaly are in agreement with the existing literature. Furthermore, we construct the one-loop effective Lagrangian from the induced energy-momentum tensor.

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Marzieh Akbari Ahmadmahmoudi, Ehsan Bavarsad. 2021-02-05. Energy-momentum tensor and effective Lagrangian of scalar QED with a nonminimal coupling in 2D de Sitter spacetime. https://doi.org/10.1103/physrevd.103.105009

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