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arXiv · 2104.12713

Covariant Effective Action for Scalar-Tensor Theories of Gravity

Sandeep Aashish·Sukanta Panda·Abbas Altafhussain Tinwala·Archit Vidyarthi
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Abstract

We develop the calculation of the divergent part of one-loop covariant effective action for scalar fields minimally and non-minimally coupled to gravity using the generalized Schwinger-DeWitt technique. We derive the field-space metric using Vilkovisky's prescription and obtain new terms in the one-loop corrections which are absent in past literature with trivial choices of field-space metric. We further calculate the covariant versions of past results, obtained using the standard approach, by applying Barvinsky and Vilkovisky's extension to the ordinary Schwinger-DeWitt approach. For completeness, we study the one-loop gravitational corrections for a dilaton-extended two-field Starobinsky model and compare with known results.

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Sandeep Aashish, Sukanta Panda, Abbas Altafhussain Tinwala, Archit Vidyarthi. 2021-04-26. Covariant Effective Action for Scalar-Tensor Theories of Gravity. https://doi.org/10.1088/1475-7516/2021/10/006

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