Black hole mergers are some of the most energetic collisions in the universe, and by simulating them the scientists are able to better understand how gravitational waves are generated. The mergers occur when two or more spinning black holes are trapped in each other’s gravitational fields, orbit each other and then collide, forming one massive black hole, writes Ian O’Neill for Discovery News.
Hugely energetic events
The events are supposedly the most energetic that the universe has seen since the Big Bang, and the energy released is thought to have a distinctive signature of gravitational wave emissions. The problem is that gravitational waves are incredible difficult to observe directly. However the ability to spot them is crucial to the development of gravitational astronomy, which could greatly improve our understanding of the evolution of our universe.
Various projects are trying to detect gravitational waves, and the most well-known is the Laser Interferometer Gravitational-Wave Observatory (LIGO), which is based in Louisiana and Washington. The aim of LIGO is to detect gravitational waves which pass through the Earth, but so far it has not done so. Its sensors are being upgraded this year and there is hope that in the near future it will gather some results.
In Europe, authorities are building a similar detector known as VIRGO, and are also planning to send the LISA Pathfinder Mission into space to set up a gravitational wave detector in orbit.
Black hole precession
The simulations made by the scientists need to be compared to data collected by LIGO in order to be corroborated, with particular efforts made to model the spin and precession of binary black holes in orbit.
“Like a spinning top, black hole binaries change their direction of rotation over time, a phenomenon known as precession,” said study co-author Ulrich Sperhake. “The behavior of these black hole spins is a key part of understanding their evolution.”
It is hoped that new information about black hole mergers will come to light thanks to computer models, which will then make it easier to understand what signals detectors such as LIGO and VIRGO detect in the future. Developments in gravitational wave astronomy could give us a far better understanding of the huge collisions and interactions which influence the evolution of our entire universe.