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arXiv · 2011.02843

Multi-field inflation from single-field models

Martin Bojowald·Suddhasattwa Brahma·Sean Crowe·Ding Ding·Joseph McCracken
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Abstract

Quantization implies independent degrees of freedom that do not appear in the classical theory, given by fluctuations, correlations, and higher moments of a state. A systematic derivation of the resulting dynamical systems is presented here in a cosmological application for near-Gaussian states of a single-field inflation model. As a consequence, single-field Higgs inflation is made viable observationally by becoming a multi-field model with a specific potential for a fluctuation field interacting with the inflaton expectation value. Crucially, non-adiabatic methods of semiclassical quantum dynamics reveal important phases that can set suitable initial conditions for slow-roll inflation (in combination with the uncertainty relation), and then end inflation after the observationally preferred number of e-folds. New parameters in the interaction potential are derived from properties of the underlying background state, demonstrating how background non-Gaussianity can affect observational features of inflation or, conversely, how observations may be used to understand the quantum state of the inflaton.

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Martin Bojowald, Suddhasattwa Brahma, Sean Crowe, Ding Ding, Joseph McCracken. 2020-11-05. Multi-field inflation from single-field models. https://doi.org/10.1088/1475-7516/2021/08/047

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