Equilateral non-Gaussianity from multifield dynamics

By A. Tolley, Mark Wyman. 2009

148 citations recorded by the source corpus.

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.

Subfields: Astronomy and Astrophysics, Statistical and Nonlinear Physics

View Paper: https://www.semanticscholar.org/paper/a274bad505d088e0adb9448ddd2fb39afd6b83c8

How researchers see this paper

The researchers whose trusted networks rank it highest, strongest advocate first. Every researcher gets a different order.

In Astronomy and Astrophysics

In Statistical and Nonlinear Physics

Citations in the corpus

Large-scale bias and efficient generation of initial conditions for nonlocal primordial non-Gaussianity (2011, background): “[13] C.”