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arXiv · 1308.0331

On the power spectrum of inflationary cosmologies dual to a deformed CFT

Paul McFadden
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Abstract

We analyse slow-roll inflationary cosmologies that are holographically dual to a three-dimensional conformal field theory deformed by a nearly marginal scalar operator. We show the cosmological power spectrum is inversely proportional to the spectral density associated with the 2-point function of the trace of the stress tensor in the deformed CFT. Computing this quantity using second-order conformal perturbation theory, we obtain a holographic power spectrum in exact agreement with the expected inflationary power spectrum to second order in slow roll.

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Paul McFadden. 2013-08-01. On the power spectrum of inflationary cosmologies dual to a deformed CFT. https://doi.org/10.1007/jhep10(2013)071

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