Abstract

The Nobel Prize winning detection of gravitational waves in 2015 by the LIGO detectors marks the dawn of a new era in observational astronomy. Gravitational waves provide a qualitatively new channel to observe compact objects and dynamical features in the earlier stages of the Universe. Several dozens of gravitational-wave events have been observed by the growing network of detectors over the past few years and have already provided new insights into gamma ray bursts, the nature of gravity, black-hole populations and the cosmography of our Universe. In this talk, we will review the basics of Einstein’s general relativity and how gravitational waves arise as a prediction of his theory. We discuss the main sources of gravitational waves across the vast frequency spectrum and the detection strategies employed for their observations, and discuss the implications of a selection of the most dramatic gravitational wave events for our understanding of the physical laws that govern our universe.