A new wave of astronomy
Sir Isaac Newton famously said, “If I have seen further, it is by standing on the shoulder of giants.”
These poignant words were in reference to the collaborative effort that underpins scientific endeavour, so it was therefore fitting that on Monday 14 September 2015 a collaboration of over 1000 scientists from 16 different countries finally added the missing piece of the jigsaw to our current understanding of gravity – a theory that Newton initially proposed.
At 9:51am GMT on that Monday morning, the collaboration, known as LIGO (Laser Interferometer Gravitational-wave Observatory), detected a gravitational wave for the very first time.
The implications were profound. Not only did the detection confirm a key prediction made by Albert Einstein – another pioneer of gravitational physics – exactly 100 years ago, but kick-started a brand new era of astronomy.
Described as tiny ripples in space-time that are emitted as a result of violent cosmic events in the Universe, gravitational waves are the final confirmation of Einstein’s spectacular theory of general relativity and will allow scientists to observe stars, galaxies and the Universe’s more exotic objects in ways that have never been possible before.
The detection would not have been possible without the key contribution of scientists working at our School of Physics and Astronomy, whose knowledge and expertise enabled scientists to pick out the signal from a cacophony of background noise and decipher where in the Universe, as well as the precise time, the gravitational waves were emitted.
Since the LIGO collaboration formed over 15 years ago, Cardiff University’s Professor Bangalore Sathyaprakash, who is part of the Gravitational Physics Group, has been instrumental in studying sources of gravitational waves and developing ways to detect them.
The detection made by Professor Sathyaprakash and the rest of the collaboration has been hailed as one of the greatest scientific discoveries of the decade, a statement that has been echoed by Astronomer Royal Lord Martin Rees.
Lord Rees is one of the world’s leading astrophysicists as well as a senior figure in UK science, and knows too well the significance of this landmark discovery. He has conducted influential theoretical work on subjects as diverse as black hole formation and extragalactic radio sources, and was one of the first to predict the uneven distribution of matter in the Universe.
Lord Rees interviewed Professor Sathyaprakash about the history of gravitational waves, the efforts to detect them, and the implications for the field of astronomy now that they’ve finally been found. Read the full interview in the summer 2016 issue of Challenge Cardiff, our research magazine.
Gravitational Physics Group
For the past decade, the Gravitational Physics Group at the School of Physics and Astronomy has laid the foundations for how we go about detecting gravitational waves, developing novel algorithms and software that have now become standard search tools for detecting the elusive signals.
The group includes world-leading experts in the collision of black holes who have produced large-scale computer simulations to imitate these violent cosmic events and predict how gravitation coding the gravitational-wave signal detected by LIGO and measuring the properties of the two black holes that collided.
Along with Professor Sathyaprakash, the group consists of Professor Mark Hannam, Professor Bernard Schutz, Dr Stephen Fairhurst and Dr Patrick Sutton.