Fairbairn M, Markkanen T, Rodriguez Roman D. Horizon feedback inflation.
THE EUROPEAN PHYSICAL JOURNAL. C, PARTICLES AND FIELDS 2018;
78:347. [PMID:
30996662 PMCID:
PMC6438654 DOI:
10.1140/epjc/s10052-018-5830-0]
[Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/06/2018] [Accepted: 04/21/2018] [Indexed: 06/09/2023]
Abstract
We consider the effect of the Gibbons-Hawking radiation on the inflaton in the situation where it is coupled to a large number of spectator fields. We argue that this will lead to two important effects - a thermal contribution to the potential and a gradual change in parameters in the Lagrangian which results from thermodynamic and energy conservation arguments. We present a scenario of hilltop inflation where the field starts trapped at the origin before slowly experiencing a phase transition during which the field extremely slowly moves towards its zero temperature expectation value. We show that it is possible to obtain enough e-folds of expansion as well as the correct spectrum of perturbations without hugely fine-tuned parameters in the potential (albeit with many spectator fields). We also comment on how initial conditions for inflation can arise naturally in this situation.
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