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Title: Equilateral non-Gaussianity from multifield dynamics

Abstract

The distinctive features of single field inflationary models with nonminimal kinetic terms, like Dirac-Born-Infeld and k inflation, can be captured by more familiar multiple-field inflationary systems of the type that typically arise in low-energy supergravity models. At least one heavy field, which we call the gelaton, has an effective potential which depends on the kinetic energy of the inflaton. Integrating out the gelaton gives rise to an effectively single field system for which the speed of sound for the adiabatic fluctuations is reduced, generating potentially observable equilateral non-Gaussianity, while causing negligible isocurvature fluctuations. This mechanism is only active if there is a relatively tight coupling between the gelaton and the inflaton. Requiring that the inflaton-gelaton system remains weakly coupled puts an upper limit on the gelaton mass. This approach gives a potentially UV-completable framework for describing large classes of k-inflationary behavior.

Authors:
;  [1]
  1. Perimeter Institute for Theoretical Physics, 31 Caroline St. N, Waterloo, Ontario N2L 2Y5 (Canada)
Publication Date:
OSTI Identifier:
21409256
Resource Type:
Journal Article
Journal Name:
Physical Review. D, Particles Fields
Additional Journal Information:
Journal Volume: 81; Journal Issue: 4; Other Information: DOI: 10.1103/PhysRevD.81.043502; (c) 2010 The American Physical Society; Journal ID: ISSN 0556-2821
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; 72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; BORN-INFELD THEORY; COUPLING; FLUCTUATIONS; INFLATIONARY UNIVERSE; KINETIC ENERGY; MASS; POTENTIALS; SOUND WAVES; SUPERGRAVITY; VELOCITY; COSMOLOGICAL MODELS; ENERGY; FIELD THEORIES; MATHEMATICAL MODELS; UNIFIED-FIELD THEORIES; VARIATIONS

Citation Formats

Tolley, Andrew J, and Wyman, Mark. Equilateral non-Gaussianity from multifield dynamics. United States: N. p., 2010. Web. doi:10.1103/PHYSREVD.81.043502.
Tolley, Andrew J, & Wyman, Mark. Equilateral non-Gaussianity from multifield dynamics. United States. https://doi.org/10.1103/PHYSREVD.81.043502
Tolley, Andrew J, and Wyman, Mark. Mon . "Equilateral non-Gaussianity from multifield dynamics". United States. https://doi.org/10.1103/PHYSREVD.81.043502.
@article{osti_21409256,
title = {Equilateral non-Gaussianity from multifield dynamics},
author = {Tolley, Andrew J and Wyman, Mark},
abstractNote = {The distinctive features of single field inflationary models with nonminimal kinetic terms, like Dirac-Born-Infeld and k inflation, can be captured by more familiar multiple-field inflationary systems of the type that typically arise in low-energy supergravity models. At least one heavy field, which we call the gelaton, has an effective potential which depends on the kinetic energy of the inflaton. Integrating out the gelaton gives rise to an effectively single field system for which the speed of sound for the adiabatic fluctuations is reduced, generating potentially observable equilateral non-Gaussianity, while causing negligible isocurvature fluctuations. This mechanism is only active if there is a relatively tight coupling between the gelaton and the inflaton. Requiring that the inflaton-gelaton system remains weakly coupled puts an upper limit on the gelaton mass. This approach gives a potentially UV-completable framework for describing large classes of k-inflationary behavior.},
doi = {10.1103/PHYSREVD.81.043502},
url = {https://www.osti.gov/biblio/21409256}, journal = {Physical Review. D, Particles Fields},
issn = {0556-2821},
number = 4,
volume = 81,
place = {United States},
year = {2010},
month = {2}
}