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Inflation parameters from Gauss-Bonnet braneworld

Hungsoo Kim·Kyong Hee Kim·Hyung Won Lee·Yun Soo Myung
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Abstract

We calculate the spectral index and tensor-to-scalar ratio for patch inflation arisen from the Gauss-Bonnet braneworld scenario. The patch cosmological models consist of Gauss-Bonnet (GB), Randall-Sundrum (RS), and 4D general relativistic (GR) cases. In order to compare with the observation data, we perform leading-order calculations for all patch models by choosing large-field, small-field, and hybrid potentials. We show that the large-field potentials are sensitive to a given patch model, while the small-field and hybrid potentials are insensitive to a given patch model. It is easier to discriminates between quadratic potential and quartic potential in the GB model rather than RS and GR models. Irrespective of patch models, it turns out that the small-field potentials are the promising models in view of the observation.

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Hungsoo Kim, Kyong Hee Kim, Hyung Won Lee, Yun Soo Myung. 2005-01-06. Inflation parameters from Gauss-Bonnet braneworld. https://doi.org/10.1016/j.physletb.2005.01.019

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