GRAVITATIONAL WAVES

A remarkable discovery has been made by radio astronomers from the Harvard-Smithsonian center for Astrophysics, Massachusetts. They found evidence of primordial gravitational waves imprinted on the cosmic microwave background (CMB), a field of energy pervading the universe. Gravitational waves are a prediction of Einstein's general theory of relativity, which is the modern theory of gravity. They have never seen directly, though an indirect proof of their existence, based on studying a pair of collapsed stars, was rewarded with the 1993 Novel Prize in physics. This discovery has not changed this state of affairs. But they have inferred the wave presence from their effect on the cosmic microwave background radiation- a faint afterglow of the universe's hot youth that now forms an electromagnetic mist which pervades the cosmos. on February 11, 2016, LIGO ( Laser Interferometer Gravitational-wave Observatory) Scientific Collaboration and Virgo Collaboration teams confirmed the directly detection of Gravitational waves from the inward spiral and merger of a pair of black holes. This is one of the biggest discovery of modern theory of gravity. Gravitational waves had previously been observed only indirectly, through their effect on the timing of pulsars in binary systems.

• About 14 billion years ago, the universe was packed into a very small, hot and dense volume that exposed, releasing lots of energy. this is the Big-Bang.

• About 30:36 second later, the universe's expansion briefly accelerated before slowing down. This was the cosmic inflation, described by group of theories.

• About 3,80,000 years later, matter had started to clump together to let energy from the Bang pass through the universe uninhibited. This residual energy is called the cosmic Microwave Background (CMB).

• If cosmos inflation had happened; it would have released gravitational waves rippling thought the universe. These waves would have caused some changes to the CMB.