Detecting relic gravitational waves in the CMB: A statistical bias

TL;DR

This paper discusses a statistical bias in analyzing relic gravitational waves in the CMB, highlighting how it can cause RGWs to be overlooked and proposing methods to avoid this bias.

Contribution

It identifies and explains a statistical bias in CMB data analysis that may lead to missing relic gravitational wave signals, and suggests ways to mitigate this bias.

Findings

Bias can cause RGWs to be overlooked in data analysis

Explanation of why the bias exists

Methods to avoid the bias

Abstract

Analyzing the imprint of relic gravitational waves (RGWs) on the cosmic microwave background (CMB) power spectra provides a way to determine the signal of RGWs. In this Letter, we discuss a statistical bias, which could exist in the data analysis and has the tendency to overlook the RGWs. We also explain why this bias exists, and how to avoid it.