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arXiv · 2009.04680

Stochastic non-attractor inflation

Hassan Firouzjahi·Amin Nassiri-Rad·Mahdiyar Noorbala
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Abstract

We extend the formalism of stochastic inflation to the setup of non-attractor inflation with a sound speed $c_s$. We obtain the Langevin equations for the superhorizon perturbations and calculate the stochastic corrections to curvature perturbation power spectrum. It is shown that the fractional stochastic corrections in mean number of e-folds and power spectrum are at the order of power spectrum. We also calculate the boundary crossing and the first hitting probabilities in a hypothetical dS space with two boundaries in field space. Furthermore, the stochastic corrections in power spectrum in a setup akin to eternal inflation with large diffusion term are calculated.

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Hassan Firouzjahi, Amin Nassiri-Rad, Mahdiyar Noorbala. 2020-09-10. Stochastic non-attractor inflation. https://doi.org/10.1103/physrevd.102.123504

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