@misc{10481/67227,
year = {2020},
month = {12},
url = {http://hdl.handle.net/10481/67227},
abstract = {We present the first quantum field theory model of inflation that is renormalizable in the matter sector, with a super-Hubble inflaton mass and sub-Planckian field excursions, which is thus technically natural and consistent with a high-energy completion within a theory of quantum gravity. This is done in the framework of warm inflation, where we show, for the first time, that strong dissipation can fully sustain a slow-roll trajectory with slow-roll parameters larger than unity in a way that is both theoretically and observationally consistent. The inflaton field corresponds to the relative phase between two complex scalar fields that collectively break a U(1)gauge symmetry, and dissipates its energy into scalar degrees of freedom in the warm cosmic heat bath. A discrete interchange symmetry protects the inflaton mass from large thermal corrections. We further show that the dissipation coefficient decreases with temperature in certain parametric regimes, which prevents a large growth of thermal inflaton fluctuations. We find, in particular, a very good agreement with the Planck legacy data for a simple quadratic inflaton potential, predicting a low tensor-to-scalar ratio r 10−5.},
organization = {UK Research & Innovation (UKRI)

Science & Technology Facilities Council (STFC)},
organization = {MINECO 

FIS2016-78198-P},
organization = {Junta de Andalucía

SOMM/17/6104/UGR
FQM101},
organization = {National Council for Scientific and Technological Development (CNPq)

302545/2017-4},
organization = {Carlos Chagas Filho Foundation for Research Support of the State of Rio de Janeiro (FAPERJ)

E-26/202.892/2017},
organization = {Portuguese Foundation for Science and Technology

European Commission

IF/01597/2015
PTDC/FIS-OUT/28407/2017},
organization = {CFisUC strategic project 

UID/FIS/04564/2019},
organization = {ENGAGE SKA 

POCI-01-0145-FEDER-022217},
publisher = {Elsevier},
title = {Towards a reliable effective field theory of inflation},
doi = {10.1016/j.physletb.2020.136055},
author = {Bastero Gil, Mar and Berera, Arjun and Ramos, Rudnei O. and Rosa, João G.},
}