Cosmic 21-cm Fluctuations as a Probe of Fundamental Physics

TL;DR

Cosmic 21-cm fluctuations at high redshift offer a novel observational method to detect and analyze exotic high-energy physics effects in the early universe, surpassing traditional CMB measurements in sensitivity.

Contribution

This paper proposes using 21-cm radiation fluctuations as a new probe for detecting modifications in the primordial spectrum caused by high-energy physics effects during inflation.

Findings

21-cm power spectrum can reveal effects of modified initial states.

21-cm observations can detect deviations from scale invariance during inflation.

Potential for more precise measurements than CMB anisotropies.

Abstract

Fluctuations in high-redshift cosmic 21-cm radiation provide a new window for observing unconventional effects of high-energy physics in the primordial spectrum of density perturbations. In scenarios for which the initial state prior to inflation is modified at short distances, or for which deviations from scale invariance arise during the course of inflation, the cosmic 21-cm power spectrum can in principle provide more precise measurements of exotic effects on fundamentally different scales than corresponding observations of cosmic microwave background anisotropies.