How can gravitational waves be detected?

1 Answer
May 1, 2016

With a set of four masses.


You know gravitation is a spin 2 interaction, represented by a tensor of rank two, the metrics. That means the wave is characterized by two directions. In other words it will pinch particles along one direction while spreading them along the other direction. So you place particles in a ring, and you send light back and forth between say 1 2 and 3 4, when the wave shows up, 12 will be closer so the light bouncing back and forth will be out of phase with that between 3 and 4. Such an apparatus is called an interferometer.