This month 11 people sat down to learn more about Gravitational Waves. This is a complex and difficult subject, so it was kept down to a level where you did not need a Ph.D. in Mathematics to gain a basic understanding.

We started by learning how Einstein delivered his theories of relativity and special relativity during 1905-1915. This was a new epoch of understanding with trying to understand the space-time dimensions and looking for answers. Most people remember his work as simply E= mc2 . (in fact, I believe more people remember this than Newtons law of gravity). Einstein postulated the formation of gravitational waves, but he was a sceptic as there was no way of proving their existence.

To help us understand how gravitational waves are formed we watched three short videos given by expects in their field which help to explain that gravitational waves are caused by massive explosions due to collapsing stars or two sun like bodies swirling around each other until they merge or a body being dragged into a black hole, all of which lead to massive energy storms that are emitted. The gravitational waves travel at the speed of lights in an outward direction gradually getting smaller the further they move from the source. Just like the ripples on a lake when we drop a stone into still water.

Gravitational Waves were first discovered on September 15th 2015 by LIGO (Laser Interferometer Gravitational -Wave Observatory) in the USA. At this moment in time, they were able to record the collapse of two black holes which had been circling each other rotating faster and faster until the inevitable crash. At a fraction of a second before the crash they sent out a vibration that lasted only a fifth of a second and away travelled at the speed of light. Now several billion years later LIGO picked up this vibration. LIGO used a laser that was split and deflected to travel along two 4km long arms set at right angles with reflectors at the either end. The reflected wave then returned to sensors and they were able to see if the gravitational wave had extended the arms in either direction. From this set up they were able to determine one of the arms had increased in length when there was a gravitational wave event hitting the earth. These ripples were caused by gravity as body causing deflections in the spacetime domain as it affects the spacetime domain, with bigger masses causing bigger ripples.

This initial breakthrough led to more astrophysicists and mathematicians building other apparatus which linked in with LIGO to give other correlations. It was found that whilst electromagnetic waves have very small wavelengths measured in micron, gravitational waves were being measured with wavelengths measured in kilometres.

Now there are plans to put up three satellites with links but being 2.5million miles apart to continue the search for more understanding of gravitational waves and their causes.
Trevor