Inflationary non-Gaussianities in the most general second-order scalar-tensor theories

Journal Article · Sat Oct 15 00:00:00 EDT 2011 · Physical Review. D, Particles Fields

DOI:https://doi.org/10.1103/PHYSREVD.84.083504· OSTI ID:21607863

De Felice, Antonio; Tsujikawa, Shinji ^[1]

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1. Department of Physics, Faculty of Science, Tokyo University of Science, 1-3, Kagurazaka, Shinjuku-ku, Tokyo 162-8601 (Japan)

For very general scalar-field theories in which the equations of motion are at second order, we evaluate the three-point correlation function of primordial scalar perturbations generated during inflation. We show that the shape of non-Gaussianities is well approximated by the equilateral type. The equilateral nonlinear parameter f{sub NL}{sup equil} is derived on the quasi-de Sitter background, where the slow-variation parameters are much smaller than unity. We apply our formula for f{sub NL}{sup equil} to a number of single-field models of inflation--such as k-inflation, k-inflation with Galileon terms, potential-driven Galileon inflation, nonminimal coupling models (including field-derivative coupling models), and Gauss-Bonnet gravity.

• OSTI ID: 21607863
• Journal Information: Physical Review. D, Particles Fields, Vol. 84, Issue 8; Other Information: DOI: 10.1103/PhysRevD.84.083504; (c) 2011 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); ISSN 0556-2821
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
CORRELATION FUNCTIONS
COUPLING
DE SITTER SPACE
DISTURBANCES
EQUATIONS OF MOTION
FIELD THEORIES
GRAVITATION
NONLINEAR PROBLEMS
PERTURBATION THEORY
SCALAR FIELDS
DIFFERENTIAL EQUATIONS
EQUATIONS
FUNCTIONS
MATHEMATICAL SPACE
PARTIAL DIFFERENTIAL EQUATIONS
SPACE