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arXiv · 1612.03960

Inflation in random Gaussian landscapes

Ali Masoumi·Alexander Vilenkin·Masaki Yamada
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Abstract

We develop analytic and numerical techniques for studying the statistics of slow-roll inflation in random Gaussian landscapes. As an illustration of these techniques, we analyze small-field inflation in a one-dimensional landscape. We calculate the probability distributions for the maximal number of e-folds and for the spectral index of density fluctuations $n_s$ and its running $α_s$. These distributions have a universal form, insensitive to the correlation function of the Gaussian ensemble. We outline possible extensions of our methods to a large number of fields and to models of large-field inflation. These methods do not suffer from potential inconsistencies inherent in the Brownian motion technique, which has been used in most of the earlier treatments.

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Ali Masoumi, Alexander Vilenkin, Masaki Yamada. 2017-01-05. Inflation in random Gaussian landscapes. https://doi.org/10.1088/1475-7516%2F2017%2F05%2F053

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