Relic Gravitational Waves and Their Detection

TL;DR

This paper discusses the theoretical predictions and observational prospects for detecting relic gravitational waves using current and future laser interferometers, highlighting their unique statistical signatures.

Contribution

It analyzes the expected amplitudes, spectral slopes, and detection strategies for relic gravitational waves, emphasizing the role of squeezing and cross-correlation techniques.

Findings

Detection is feasible with initial detectors via cross-correlation.

Advanced detectors will enhance sensitivity for relic wave detection.

Squeezing provides a unique statistical signature to improve detection confidence.

Abstract

The range of expected amplitudes and spectral slopes of relic (squeezed) gravitational waves, predicted by theory and partially supported by observations, is within the reach of sensitive gravity-wave detectors. In the most favorable case, the detection of relic gravitational waves can be achieved by the cross-correlation of outputs of the initial laser interferometers in LIGO, VIRGO, GEO600. In the more realistic case, the sensitivity of advanced ground-based and space-based laser interferometers will be needed. The specific statistical signature of relic gravitational waves, associated with the phenomenon of squeezing, is a potential reserve for further improvement of the signal to noise ratio.