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arXiv · 2204.04647

Self-tuning inflation

Polina Petriakova·Sergey G. Rubin
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Abstract

We develop an inflationary model without small parameters on the basis of multidimensional $f(R)$ gravity with a minimally coupled scalar field. The model is described by two stages of space expansion. The first one begins at energy scales about the D-dimensional Planck mass and ends with the de Sitter metric of our space and the maximally symmetric extra dimensions. In the following, the quantum fluctuations produce a wide set of inhomogeneous extra metrics in causally disconnected regions quickly generated in the de Sitter space. We find a specific extra space metric that leads to the effective Starobinsky model that fits the observational data.

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Polina Petriakova, Sergey G. Rubin. 2022-04-10. Self-tuning inflation. https://doi.org/10.1140/epjc/s10052-022-10983-w

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