Large-scale anomalies from primordial dissipation

TL;DR

This paper explores an inflationary model where particle production modulated by an auxiliary field explains observed hemispherical asymmetry and power suppression in the CMB, predicting specific signatures at large and small scales.

Contribution

It introduces a novel inflationary scenario linking particle production modulation to CMB anomalies, with detailed predictions for observable signatures.

Findings

Reproduces hemispherical power asymmetry observed in CMB data.

Accounts for low multipole power suppression.

Predicts small oscillations in the power spectrum at all scales.

Abstract

We analyze an inflationary model in which part of the power in density perturbations arises due to particle production. The amount of particle production is modulated by an auxiliary field. Given an initial gradient for the auxiliary field, this model produces a hemispherical power asymmetry and a suppression of power at low multipoles similar to those observed by WMAP and Planck in the CMB temperature. It also predicts an additive contribution to $\delta T$ with support only at very small $l$ that is aligned with the direction of the power asymmetry and has a definite sign, as well as small oscillations in the power spectrum at all $l$.