On the strong coupling problem in cosmologies with "strong gravity in the past"

Abstract

We examine the potential strong coupling problem at early times in a bouncing cosmological model with "strong gravity in the past" (Jordan frame), which is conformally related to inflation (Einstein frame). From naive dimensional analysis in the Jordan frame one would conclude that the quantum strong coupling energy scale can be lower than the classical energy scale. However, from the Einstein frame prospective this should not be the case. We illustrate this point by calculation in the Jordan frame which shows cancellations of the dangerous contributions in the tree level amplitude.

9 pages

References in corpus (6)

• Imperfect Dark Energy from Kinetic Gravity Braiding
• G-inflation: inflation driven by the Galileon field
• Primordial non-Gaussianities in general modified gravitational models of inflation
• Nonsingular cosmological models with strong gravity in the past
• Horndeski genesis: consistency of classical theory
• Cosmology from pregeometry

Cited by in corpus (6)

• Primordial non-Gaussianity from Galilean Genesis without strong coupling problem
• Parity violation in primordial tensor non-Gaussianities from matter bounce cosmology
• Cuscuton Bounce Beyond the Linear Regime: Bispectrum and Strong Coupling Constraints
• Can Horndeski Genesis be Nonpathological?
• K-inflation: the legitimacy of classical treatment
• Constraining matter-bounce scenario from scalar-induced vector perturbations