Astrophysicists are gaining new understanding of how gravitational waves are formed thanks to new detailed models of black hole collisions. These collisions occur when black holes get caught in one another’s gravitational wells and enter into ever-tightening orbits around each other until they merge into one.
As reported by Discovery News, mergers between black holes “are thought to be the most energetic events the universe has seen since the Big Bang.” The massive amount of energy put forth by these collisions is thought to have a unique gravitational wave emission signature.
While gravitational waves can be indirectly observed and their properties described, more conclusive data and direct observation opportunities have thus far eluded astrophysicists.
Under the guiding principles of the theory of general relativity, scientists would expect gravitational waves to be created by large objects gaining speed through space. This predicted phenomenon, however, has not been directly observed. Current evidence for the existence of gravitational waves comes in the form of space objects’ behavior. For example, when two white dwarf stars orbit one another, energy gradually becomes lost as their orbits shrink over time. The conclusion is that gravitational waves are the means by which that energy leaves the binary system.
Several devices designed to detect gravitational waves are currently in use or in development. The Laser Interferometer Gravitational-Wave Observatory (LIGO), with two locations in the United States, is currently being refitted to become more sensitive to gravitational waves that pass through Earth. Another detector known as VIRGO is being built in Europe and the LISA Pathfinder Mission will deliver a gravitational wave detector into space.
Until direct detection of gravitational waves is achieved by detectors, the study of black hole mergers may be the most promising vehicle for future breakthroughs in the science of gravitational astronomy.
“Using gravitational waves as an observational tool, you could learn about the characteristics of the black holes that were emitting those waves billions of years ago,” study co-author Davide Gerosa, of the University of Cambridge, said in a statement. “That’s important data for more fully understanding the evolution and nature of the universe.”
The University of Cambridge researchers focused their study on modelling the spin and change in rotation direction observed in colliding black holes. The team looks forward to comparing the results of their calculations regarding the kinds of waves that black hole mergers would emit with the data collected in the future by the LIGO detector. The hope is that the researchers’ models will help identify and analyze the signals coming into the detectors with speed and accuracy, bringing valuable insight into the whole realm of gravitational energy transfer that shapes the universe.