Direct Detection of the Primordial Inflationary Gravitational Waves

TL;DR

This paper discusses the potential for directly detecting primordial inflationary gravitational waves through advanced polarization observations of the CMB, which could reveal the energy scale of inflation.

Contribution

It proposes that current technology could directly observe inflationary gravitational waves with high sensitivity if foreground signals are effectively separated.

Findings

Potential to detect inflationary GWs with Omega-gw down to 10^(-23)

Use of polarization observations of CMB for direct GW detection

Feasibility depends on foreground separation techniques

Abstract

Inflationary cosmology is successful in explaining a number of outstanding cosmological issues including the flatness, the horizon and the relic issues. More spectacular is the experimental confirmation of the structure as arose from the inflationary quantum fluctuations. However, the physics in the inflationary era is unclear. Polarization observations of Cosmic Microwave Background (CMB) missions may detect the tensor mode effects of inflationary gravitational waves (GWs) and give an energy scale of inflation. To probe the inflationary physics, direct observation of gravitational waves generated in the inflationary era is needed. In this essay, we advocate that the direct observation of these GWs with sensitivity Omega-gw down to 10**(-23) is possible using present projected technology development if foreground could be separated.