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arXiv · 1509.01247

Non-local gravity in D-dimensions: Propagator, entropy and bouncing Cosmology

Aindriu Conroy·Anupam Mazumdar·Spyridon Talaganis·Ali Teimouri
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Abstract

We present the graviton propagator for an infinite derivative, $D$-dimensional, non-local action, up to quadratic order in curvature around a Minkowski background, and discuss the conditions required for this class of gravity theory to be ghost-free. We then study the gravitational entropy for de-Sitter and Anti-de Sitter backgrounds, before comparing with a recently derived result for a Schwarzschild blackhole, generalised to arbitrary $D$-dimensions, whereby the entropy is given simply by the area law. A novel approach of decomposing the entropy into its $(r, t)$ and spherical components is adopted in order to illustrate the differences more clearly. We conclude with a discussion of de-Sitter entropy in the framework of a non-singular bouncing cosmology.

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Aindriu Conroy, Anupam Mazumdar, Spyridon Talaganis, Ali Teimouri. 2015-11-26. Non-local gravity in D-dimensions: Propagator, entropy and bouncing Cosmology. https://doi.org/10.1103/physrevd.92.124051

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