TY - JOUR

T1 - The phenomenology of trapped inflation

AU - Pearce, Lauren

AU - Peloso, Marco

AU - Sorbo, Lorenzo

N1 - Publisher Copyright:
© 2016 IOP Publishing Ltd and Sissa Medialab srl.

PY - 2016/11/28

Y1 - 2016/11/28

N2 - Trapped inflation is a mechanism in which particle production from the moving inflaton is the main source of friction in the inflaton equation of motion. The produced fields source inflaton perturbations, which dominate over the vacuum ones. We review the computation of the perturbations performed in the original work and in a successive analysis that makes use of the effective field theory (EFT) of inflation. This second paper employs the power spectrum of the inflaton perturbations obtained in the original work, and obtains a bispectrum which parametrically agrees with that of the original work, even if it originates from a different operator. We show that one approximation used in the original work to compute the correlators of the produced quanta is invalid. We replace this approximation with an exact solution of the system of equations developed in the original work and obtain a different amplitude for the power spectrum of the inflaton perturbations, which has a significant consequence for the allowed region of parameter space in this mechanism. We then show that the operator responsible for the bispectrum in the EFT computation does not arise from the computational scheme developed in the original paper and that the agreement between the bispectra of the two works is also caused by the invalid approximation.

AB - Trapped inflation is a mechanism in which particle production from the moving inflaton is the main source of friction in the inflaton equation of motion. The produced fields source inflaton perturbations, which dominate over the vacuum ones. We review the computation of the perturbations performed in the original work and in a successive analysis that makes use of the effective field theory (EFT) of inflation. This second paper employs the power spectrum of the inflaton perturbations obtained in the original work, and obtains a bispectrum which parametrically agrees with that of the original work, even if it originates from a different operator. We show that one approximation used in the original work to compute the correlators of the produced quanta is invalid. We replace this approximation with an exact solution of the system of equations developed in the original work and obtain a different amplitude for the power spectrum of the inflaton perturbations, which has a significant consequence for the allowed region of parameter space in this mechanism. We then show that the operator responsible for the bispectrum in the EFT computation does not arise from the computational scheme developed in the original paper and that the agreement between the bispectra of the two works is also caused by the invalid approximation.

UR - http://www.scopus.com/inward/record.url?scp=85006074988&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=85006074988&partnerID=8YFLogxK

U2 - 10.1088/1475-7516/2016/11/058

DO - 10.1088/1475-7516/2016/11/058

M3 - Article

AN - SCOPUS:85006074988

VL - 2016

JO - Journal of Cosmology and Astroparticle Physics

JF - Journal of Cosmology and Astroparticle Physics

SN - 1475-7516

IS - 11

M1 - 058

ER -