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arXiv · 0905.0543

One-loop effective action for non-local modified Gauss-Bonnet gravity in de Sitter space

Guido Cognola·Emilio Elizalde·Shin'ichi Nojiri·Sergei D. Odintsov·Sergio Zerbini
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Abstract

We discuss the classical and quantum properties of non-local modified Gauss-Bonnet gravity in de Sitter space, using its equivalent representation via string-inspired local scalar-Gauss-Bonnet gravity with a scalar potential. A classical, multiply de Sitter universe solution is found where one of the de Sitter phases corresponds to the primordial inflationary epoch, while the other de Sitter space solution--the one with the smallest Hubble rate--describes the late-time acceleration of our universe. A Chameleon scenario for the theory under investigation is developed, and it is successfully used to show that the theory complies with gravitational tests. An explicit expression for the one-loop effective action for this non-local modified Gauss-Bonnet gravity in the de Sitter space is obtained. It is argued that this effective action might be an important step towards the solution of the cosmological constant problem.

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Guido Cognola, Emilio Elizalde, Shin'ichi Nojiri, Sergei D. Odintsov, Sergio Zerbini. 2009-09-01. One-loop effective action for non-local modified Gauss-Bonnet gravity in de Sitter space. https://doi.org/10.1140/epjc%2Fs10052-009-1154-4

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