Theory-Agnostic Constraints on Black-Hole Dipole Radiation with Multi-Band Gravitational-Wave Astrophysics

TL;DR

This paper discusses how multi-band gravitational-wave observations can significantly improve constraints on black-hole dipole radiation, testing gravity theories beyond current limits.

Contribution

It introduces a theory-agnostic framework for constraining black-hole dipole radiation using combined aLIGO and eLISA data, enhancing bounds by six orders of magnitude.

Findings

Joint GW observations can vastly improve dipole radiation constraints.

Multi-band GW data can test gravity theories beyond current limits.

Constraints depend on eLISA's operational status.

Abstract

The aLIGO detection of the black-hole binary GW150914 opened a new era for probing extreme gravity. Many gravity theories predict the emission of dipole gravitational radiation by binaries. This is excluded to high accuracy in binary pulsars, but entire classes of theories predict this effect predominantly (or only) in binaries involving black holes. Joint observations of GW150914-like systems by aLIGO and eLISA will improve bounds on dipole emission from black-hole binaries by six orders of magnitude relative to current constraints, provided that eLISA is not dramatically descoped.