Everything You Need To Know About Gravitational Waves

These questions originally appeared on Quorathe knowledge sharing network where compelling questions are answered by people with unique insights.

Answers by Peter Graham, Stanford Physics Professor and Gravitational Wave Researcher, on Quora.

Q: How important is the discovery of Gravitational Waves?

A: Extremely important! This is surely one of the most important discoveries in physics in the past several decades. It is not even so much the confirmation of the gravitational waves themselves, we were very confident that they existed, it is that we now have the ability to observe the universe using this entirely new spectrum. Everything we currently know about astrophysics and cosmology arose from observations of electromagnetic waves. Gravitational waves give us a new and entirely different source of information. We will learn a great deal about the universe that we could never have learned any other way.

Q: How did LIGO validate the signal they detected?

A: This is a very important question, and also very complicated. In fact, for the real answer I recommend reading the papers that LIGO put out. Here I can just give some of the basic ideas of how it is done. When looking for such a small signal, it is absolutely crucial not to fool yourself because there is always a lot of noise in such a precise measurement. The LIGO collaboration worked very hard for a long time to make sure that they could claim a detection with confidence when it occurred. There are many possible problems with making such a detection and so LIGO applies many different strategies for dealing with these problems. A few of these are as follows. First they built two detectors, one in Washington and one in Louisiana, and required that both detectors see the same signal —> Read More