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arXiv · 1402.5075

Starobinsky-Like Inflation in Dilaton-Brane Cosmology

John Ellis·Nick E. Mavromatos·Dimitri V. Nanopoulos
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Abstract

We discuss how Starobinsky-like inflation may emerge from dilaton dynamics in brane cosmology scenarios based on string theory, in which our universe is represented as a three-brane. The effective potential may acquire a constant term from a density of effectively point-like non-pertubative defects on the brane. Higher-genus corrections generate corrections to the effective potential that are exponentially damped at large field values, as in the Starobinsky model, but at a faster rate, leading to a smaller prediction for the tensor-to scalar perturbation ratio r. This may be compensated partially by logarithmic deformations on the world-sheet due to recoil of the defects due to scattering by string matter on the brane, which tend to enhance the tensor-to-scalar ratio.

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John Ellis, Nick E. Mavromatos, Dimitri V. Nanopoulos. 2014-04-07. Starobinsky-Like Inflation in Dilaton-Brane Cosmology. https://doi.org/10.1016/j.physletb.2014.04.014

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