LIGO - Is there any field called "Gravitational" exist

Since few days we are hearing about National Science Foundation's news about LIGO. So in this article we will see what is LIGO project and how it works. 

In the famous story of scientist Newton had found the gravitational force exist by which the apple is fall on ground from the tree. That was the fist time in 1687 the gravity was introduced to the general people by the sir Isaac Newton. He formulated the gravity in f=ma formula. After two more century's that is in 1918 sir Einstein had restated a gravity as a "fictitious force to the curvature of spacetime" in his theory of relativity. And now after a century the scientist had succeeded in the discovery of gravitational waves in Laser Interferometer Gravitational-wave Observatory (LIGO) project. 

How LIGO operates ?

  Actually a LIGO does not detect the gravitational waves it just observes it. It has detected a gravitational waves created from the collision between two black oles which are thousands of light year away from the earth. LIGO is a tyoe of telescope that uses gravitational waves instead of electromagnetic waves detecting the source of gravitational field.

  It works like a blind person detecting a number of sound source by its intensity, the LIGO also detecting all types of electromagnetic waves (infrared, radio, visible, UV, X-ray), same we can also detect gravitational waves.

  To spot a signal, LIGO uses a special mirror to split a beam of laser light and sends the beams down two 4-kilometer-long arms, at a 90 degree angle to each other. After ricocheting back and forth 400 times, turning each beam’s journey into a 1,600 kilometer round-trip, the light recombines near its source.

Since this gravitational waves energy is equally distributed in all directions and decreases as the distance increases to the double same as the water waves.