Gravitational Waves: A New Astronomy

TL;DR

The paper discusses the revolutionary impact of gravitational wave detection on astronomy, enabling new insights into black hole and neutron star mergers, and facilitating tests of fundamental physics and cosmology.

Contribution

It highlights recent discoveries in gravitational wave astronomy, emphasizing the transition to multi-messenger observations and their implications for physics and cosmology.

Findings

Detection of black hole mergers by LIGO/Virgo since 2015

Observation of neutron star mergers with electromagnetic counterparts in 2017

Advancement of multi-messenger astronomy integrating gravitational and electromagnetic data

Abstract

Contemporary astronomy is undergoing a revolution, perhaps even more important than that which took place with the advent of radioastronomy in the 1960s, and then the opening of the sky to observations in the other electromagnetic wavelengths. The gravitational wave detectors of the LIGO/Virgo collaboration have observed since 2015 the signals emitted during the collision and merger of binary systems of massive black holes at a large astronomical distance. This major discovery opens the way to the new astronomy of gravitational waves, drastically different from the traditional astronomy based on electromagnetic waves. More recently, in 2017, the detection of gravitational waves emitted by the inspiral and merger of a binary system of neutron stars has been followed by electromagnetic signals observed by the $\gamma$ and X satellites, and by optical telescopes. A harvest of discoveries has been possible thanks to the multi-messenger astronomy, which combines the information from the gravitational wave with that from electromagnetic waves. Another important aspect of the new gravitational astronomy concerns fundamental physics, with the tests of general relativity and alternative theories of gravitation, as well as the standard model of cosmology.