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arXiv · 1402.4964

UV-extending Ghost Inflation

Mikhail M. Ivanov·Sergey Sibiryakov
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Abstract

We present a setup that provides a partial UV-completion of the ghost inflation model up to a scale which can be almost as high as the Planck mass. This is achieved by coupling the inflaton to the Lorentz-violating sector described by the Einstein-aether theory or its khronometric version. Compared to previous works on ghost inflation our setup allows to go beyond the study of small perturbations and include the background dynamics in a unified framework. In the specific regime when the expansion of the Universe is dominated by the kinetic energy of the inflaton we find that the model predicts rather high tensor-to-scalar ratio r ~ 0.02 $÷$ 0.2 and non-Gaussianity of equilateral type with f_NL in the range from -50 to -5.

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Mikhail M. Ivanov, Sergey Sibiryakov. 2014-05-23. UV-extending Ghost Inflation. https://doi.org/10.1088/1475-7516%2F2014%2F05%2F045

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