Hilltops
Hartwick College's Student Newspaper

The View From Oyaron Hill

Gravity Waves

03.15.16


Josh White


I am sure that everyone is familiar with the emails that were received on February, 11 regarding the possible detection of gravity waves.


Now some of you may have had a few questions such as: “What are gravity waves?” or “What does their detection mean?”, Or even “Why should I care about gravity waves?”


According to Albert Einstein’s general theory of relativity, a gravity wave is a ripple in the fabric of space-time. This theory also states that gravity itself can be understood as a warping of space, and when gravitating objects move they produce gravity waves.  Theoretically these waves will compress and stretch the local space as they pass through. LIGO (Laser Interferometer Gravitational-wave Observatory) detectors use lasers which are shot through an airless 4km long tube and measure the reflection of light by using mirrors.


This allows scientists to detect changes in the distance between the mirrors, which would indicate gravity waves. This method is incredibly sensitive, trying to measure the displacement of less than a millionth the size of an atom, which is why two of these detectors are used over 2,000 miles apart. These waves are so weak because gravity is an incredibly weak force. Even the attraction between stars and planets can’t be detected. So this leaves something with an incredibly high gravity, black holes.


It is thought that two black holes coalescing into one produced the gravity waves detected. The first gravitational waves were detected on September 14, 2015 and it was announced on February 11, 2016. This opens up a new kind of astronomy, in which scientists can look at the dynamics of space itself instead of the matter inside of it.