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arXiv · 2003.09610

R-summed form of adiabatic expansions in curved spacetime

Antonio Ferreiro·Jose Navarro-Salas·Silvia Pla
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Abstract

The Feynman propagator in curved spacetime admits an asymptotic (Schwinger-DeWitt) series expansion in derivatives of the metric. Remarkably, all terms in the series containing the Ricci scalar R can be summed exactly. We show that this (non-perturbative) property of the Schwinger-DeWitt series has a natural and equivalent counterpart in the adiabatic (Parker-Fulling) series expansion of the scalar modes in an homogeneous cosmological spacetime. The equivalence between both R-summed adiabatic expansions can be further extended when a background scalar field is also present.

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Antonio Ferreiro, Jose Navarro-Salas, Silvia Pla. 2020-03-21. R-summed form of adiabatic expansions in curved spacetime. https://doi.org/10.1103/physrevd.101.105011

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