Gravitational Waves

Up until about two years ago, gravitational waves were rarely discussed outside of the scientists who based their careers on its discovery. To the public, the entire phenomena was unknown. However, that quickly changed on September 14, 2015 when the Laser Interferometer Gravitational-Wave observatory directly detected gravitational waves. As this news spread across the globe, many people were left asking questions rather than celebrating. What are gravitational waves? Where do they come from? And how in the world did we manage to detect one?

A depiction of gravitational waves emanating from two orbiting black holes

Gravitational waves were first postulated by Albert Einstein as a direct result of general relativity. His work showed that large, accelerating objects can disturb the fabric of space-time so much that waves emanate from the source, rippling through space. Although these waves can be an indication of the release of massive amounts of energy, they appear to be harmless by the time we receive them on Earth. The sources of these gravitational waves can vary, but they all tend to be situations in space where massive amounts of energy are given off. For a more comprehensive list of sources, please click on the link provided below. Finally, direct detection of gravitational waves on Earth proved to be very difficult indeed. LIGO was able to detect these tiny gravitational waves through the use of an interferometer, similar (although much larger) to the one used by Michelson and Morley in their famous experiment (As discussed in my previous blog post). This interferometer is so precise that it was able to detect graviational waves thousands of times smaller than a nucleus. One thing is for certain, much can be learned from these gravitational waves, and scientists will continue to study them for decades to come.

Source: LIGO and Gravitational Waves