Gravitational waves are disturbances in the fabric of spacetime. If you drag your hand through a still pool of water, you’ll notice that waves follow in its path, and spread outward through the pool. According to Albert Einstein, the same thing happens when heavy objects move through spacetime.
According to Einstein’s General Theory of Relativity, any accelerating mass should produce ripples in the fabric of space and time.
Gravitational waves provide a completely new way at looking at the Universe. The ability to detect them has the potential to revolutionise astronomy.
Gravitational waves are a signal that comes right from black holes themselves and carries information about them. In this sense, you can argue that we have just made the first direct detection of black holes as well.
Krauss said he was 60% confident that the rumour was true, but said he would have to see the scientists’ data before drawing any conclusions about whether the signal was genuine or not.
Einstein predicted that the waves would be produced in extremely violent events, such as collisions between two black holes. As gravitational waves spread out, they compress and stretch spacetime.