Gravitational waves, dark energy and inflation

TL;DR

This paper classifies gravitational waves by frequency, reviews detection methods and space missions, and discusses how gravitational wave observations can inform dark energy and inflationary physics.

Contribution

It provides a comprehensive classification of gravitational wave frequencies and discusses their detection and implications for dark energy and inflation.

Findings

Classification of gravitational waves into nine frequency bands.

Overview of space-based gravitational wave detectors and missions.

Discussion on probing dark energy and inflation with gravitational waves.

Abstract

In this paper we first present a complete classification of gravitational waves according to their frequencies: (i) Ultra high frequency band (above 1 THz); (ii) Very high frequency band (100 kHz - 1 THz); (iii) High frequency band (10 Hz - 100 kHz); (iv) Middle frequency band (0.1 Hz - 10 Hz); (v) Low frequency band (100 nHz - 0.1 Hz); (vi) Very low frequency band (300 pHz - 100 nHz); (vii) Ultra low frequency band (10 fHz - 300 pHz); (viii) Hubble (extremely low) frequency band (1 aHz - 10 fHz); (ix) Infra-Hubble frequency band (below 1 aHz). After briefly discussing the method of detection for different frequency bands, we review the concept and status of space gravitational-wave missions --- LISA, ASTROD, ASTROD-GW, Super-ASTROD, DECIGO and Big Bang Observer. We then address to the determination of dark energy equation, and probing the inflationary physics using space gravitational wave detectors.