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arXiv · 1503.01579

Gauss-Bonnet Inflation

Panagiota Kanti·Radouane Gannouji·Naresh Dadhich
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Abstract

We consider an Einstein-Scalar-Gauss-Bonnet gravitational theory, and argue that at early times the Ricci scalar can be safely ignored. We then demonstrate that the pure scalar-Gauss-Bonnet theory, with a quadratic coupling function, naturally supports inflationary -- de Sitter -- solutions. During inflation, the scalar field decays exponentially and its effective potential remains always bounded. The theory contains also solutions where these de Sitter phases possess a natural exit mechanism and are replaced by linearly expanding -- Milne -- phases.

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Panagiota Kanti, Radouane Gannouji, Naresh Dadhich. 2015-03-05. Gauss-Bonnet Inflation. https://doi.org/10.1103/physrevd.92.041302

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