Correlating CMB Spectral Distortions with Temperature: what do we learn on Inflation?

TL;DR

This paper explores how correlating CMB spectral distortions with temperature anisotropies can provide new insights into inflation by testing squeezed limit bispectra across a broad range of scales, potentially constraining various inflationary models.

Contribution

It introduces a method to constrain inflationary models through spectral distortion-temperature correlations, extending the scale range for testing squeezed limits.

Findings

Predicted bispectra amplitudes are above PIXIE sensitivity.

Correlations can test inflationary mechanisms across new scales.

Provides quantitative predictions for specific inflationary models.

Abstract

Probing correlations among short and long-wavelength cosmological fluctuations is known to be decisive for deepening the current understanding of inflation at the microphysical level. Spectral distortions of the CMB can be caused by dissipation of cosmological perturbations when they re-enter Hubble after inflation. Correlating spectral distortions with temperature anisotropies will thus provide the opportunity to greatly enlarge the range of scales over which squeezed limits can be tested, opening up a new window on inflation complementing the ones currently probed with CMB and LSS. In this paper we discuss a variety of inflationary mechanisms that can be efficiently constrained with distortion-temperature correlations. For some of these realizations (representative of large classes of models) we derive quantitative predictions for the squeezed limit bispectra, finding that their amplitudes are above the sensitivity limits of an experiment such as the proposed PIXIE.