When Black holes & Neutron Stars Collide – Brian Cox on Gravitational Waves
When Black holes & Neutron Stars Collide – Brian Cox on Gravitational Waves
More than 100 years ago, Albert Einstein came up with many ideas about gravity and space. In Einstein’s general theory of relativity, gravity is treated as a phenomenon resulting from the curvature of spacetime. This curvature is caused by the presence of mass. Generally, the more mass that is contained within a given volume of space, the greater the curvature of spacetime will be at the boundary of its volume.
English physicist and professor of particle physics in the School of Physics and Astronomy at the University of Manchester, Brian Cox explains the science behind gravitational waves. He mentions how every massive object that accelerates produces gravitational waves. Brian Cox also explains in layman terms how LIGO is able to detect gravitational waves caused by some of the most energetic events in the Universe—colliding black holes, merging neutron stars, exploding stars, and possibly even the birth of the Universe itself.
100 years after Einstein came up with the general theory of relativity, scientists detected gravitational waves for the first time. These first gravitational waves happened when two black holes crashed into one another.
The two blackholes that merged formed a single blackhole 62 times the mass of our sun. As they merged in about 0.2 seconds the equivalent of 3 times the mass of our Sun was lost through gravitational waves emission. In comparison our Sun has lost a mere 0.03 percent of its mass in 5 billion years through electromagnetic emission.
Many models of the Universe suggest that there was an inflationary epoch in the early history of the Universe when space expanded by a large factor in a very short amount of time. If this expansion was not symmetric in all directions, it may have emitted gravitational radiation detectable today as a gravitational wave background. This background signal is too weak for any currently operational gravitational wave detector to observe. However, LIGO is just the first step and with future instruments we could potentially pickup gravitational waves that rippled through the first moments of the Big Bang that would solve one of the greatest mysteries in physics.