The Detection of Gravitational Waves


Gravitational Waves
Posted on 12 February 2016

Scientists have announced the detection of gravitational waves, confirming Albert Einstein’s theory of relativity from 100 years ago. We asked Professor of Astrophysics at Keele, Professor Rob D. Jeffries, to comment on the discovery:

"Gravitational waves are wave-like distortions (rapid stretching and contracting) of space that are generated by the motions of massive objects (in the case of yesterday's discovery, a pair of coalescing black holes) and travel outwards into the universe.

The discovery opens up a brand new way of studying the universe. Gravitational waves can travel through any object or material unimpeded and will tell us about things that are otherwise shielded from view (e.g. the core of a supernova explosion) or are dark (e.g. black holes). Since they travel at the speed of light and can be detected at great distance, there is even the potential to "see" events in the very distant past using gravitational waves (the event announced yesterday happened 1.3 billion years ago), perhaps even right back to the big bang itself. On a more fundamental level, the detection is a triumph for the theory of General Relativity, which has passed a most stringent test with flying colours.

Keele students learn about oscillations and waves very early in the course, much of which applies to electromagnetic waves, gravitational waves or even waves on the ocean. In year 2 they learn about the optical techniques that were used to detect the gravitational waves (interferometry). There is a year 3 option course on the physics of white dwarfs, black holes and neutron stars.

Gravitational waves have the potential to revolutionize the study of these objects and I will be having to update some lectures! For example, the black holes that were announced yesterday were the most massive black holes ever found that were likely produced as a result of the deaths of massive stars, and it was the first black hole merger to have been witnessed directly.

Most of Keele's research involves stars and (exo)planets - the gravitational waves produced by such objects are likely to be too weak for detection even in the medium term. However, some of our research focuses on supermassive black holes in distant galaxies. It is quite probable that space-borne interferometers will now be funded that will allow us to uncover much more about the mysterious birth and evolution of such objects.”