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Non-vacuum initial states for the cosmological perturbations and the back-reaction problem of inflation

Alejandro Gangui·Jerome Martin·Mairi Sakellariadou
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Abstract

In the framework of Inflationary theory, the assumption that the quantum state of the perturbations is a non-vacuum state leads to a difficulty: non-vacuum initial states imply, in general, a large energy density of inflaton field quanta, not of a cosmological term type, that could prevent the inflationary phase. In this short note, we discuss in detail why this is so, keeping an eye on possible non-Gaussian features due to considering generic non-vacuum initial states.

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Alejandro Gangui, Jerome Martin, Mairi Sakellariadou. 2002-06-03. Non-vacuum initial states for the cosmological perturbations and the back-reaction problem of inflation. https://arxiv.org/abs/astro-ph/0206023

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