Cottrell College Science Awards - 2015
Spin and Horizon Multipoles in Numerical Relativity, and the Visualization of Dynamical Spacetimes
Black holes have such a strong gravitational pull that nothing -- no particle or electromagnetic radiation -- can escape from them. Not only can black holes be massive, many times the mass of our sun, they can rotate very rapidly. In the constellation Aquila, for example, a black hole with 10 to 15 solar masses is estimated to be rotating 950 times each second.
Theoretically, two spinning black holes orbiting each other are capable of producing ripples in the curvature of spacetime -- in other words, gravitational waves. (Einstein’s General Theory of Relativity predicts the accelerating masses of the two black holes produce this effect, much like an accelerating electron produces electromagnetic radiation.) But so far these gravitational waves have not been directly detected. That is the next big physics discovery scientists hope to achieve.
An accurate knowledge of black hole angular momentum (i.e., momentum of rotation which depends on mass, shape and speed) and related characteristics will help scientists detect and understand the still-elusive phenomenon of gravitational waves. Hopeful observers predict that research projects such as Advanced LIGO and NANOGrav are likely to detect gravitational waves in the cosmos within the next few years.
Robert Owen, assistant professor of physics & astronomy at Oberlin College, is participating in this effort. Owen has received a Cottrell College Science Award from Research Corporation for Science Advancement to develop detailed supercomputer models of black holes, their angular momentum and interactions, as the sources of strong gravitational waves.
Owen says these models are needed to provide templates of waveforms that will help observers recognize and understand how black holes generate gravitational waves, when they are detected.
Eventually, if scientists perfect the detection and understanding of gravitational waves, they could directly measure some of the most violent events in the universe: collisions of black holes and neutron stars, and obtain the clearest picture yet of the behavior of the gravitational field in strongly dynamical circumstances, an aspect of Einstein's theory of relativity that, even after a century of study, still has not been probed observationally.