Adiabatic regularisation of power spectrum in nonminimally coupled general single-field inflation [CL]

http://arxiv.org/abs/1709.06450


We perform adiabatic regularisation of power spectrum in nonminimally coupled general single-field inflation with varying speed of sound. The subtraction is performed within the framework of earlier study by Urakawa and Starobinsky dealing with the canonical inflation. Inspired by Fakir and Unruh’s model on nonminimally coupled chaotic inflation, we find upon imposing near scale invariance condition, that the subtraction term exponentially decays with the number of $ e $-folds. As in the result for the canonical inflation, the regularised power spectrum tends to the “bare” power spectrum as the Universe expands during (and even after) inflation. This work justifies the use of the “bare” power spectrum in standard calculation in the most general context of slow-roll single-field inflation involving non-minimal coupling and varying speed of sound.

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A. Alinea
Wed, 20 Sep 17
33/57

Comments: version 1.0, 19 pages