Discovery of gravitational waves
The disturbance in the space-time curvature due to the acceleration of the heavy bodies is called gravitational waves.
The disturbance or energy, that releases from heavy accelerated bodies travel with the speed of light.
In 1905 Jules Henri Poincare the French scientist was proposed gravitational waves.
In 1916 Albert Einstein Subsequently predicted Gravitational waves on the basis of his general theory of relativity.
These waves propagate energy in the form of gravitational radiation.
The form of gravitational radiant energy is similar to electromagnetic radiation.
Newton’s gravitational law does not provide evidence for their existence since that law is predicated on the assumption that heavy bodies radiation accelerate instantaneously (at infinite speed).
Gravitational-wave astronomy is the branch of observational astronomy science.
that use gravitational waves to collect observational data about sources of detectable gravitational waves.
Such as binary star systems composed of white dwarfs, black holes and neutron stars;
and events like as supernovae, and the formation about the early universe after the Big Bang.
In 1993, the American scientist Russell A. Hulse and Joseph H. Taylor, Jr. received the Nobel Prize in Physics for the discovery of the Hulse-Taylor binary pulsar,
which was the first indirect evidence of the existence of gravitational waves.
This neutron are losing orbital energy through the emission of gravitational waves,
which causes the orbit of the binary to shrink;
the rate of decrease in the orbital period that is predicted by general relativity agrees exquisitely with the measured value.
A number of similar binaries were later found and observed with even greater precision,
lending further credence to gravitational waves and their description in the underlying theory.
The detection of gravitational waves in more direct senses is very difficult,
due to the weak coupling between gravity and matter.
Efforts to directly detect astrophysical gravitational waves began with the resonant detectors of the 1960s,
which were designed to pick up resonantly ampliﬁed antenna oscillations caused by passing waves.
Although unsuccessful, these attempts paved the way for the adoption of laser interferometry in gravitational waves detection,
and the eventual construction of large-scale interferometers such as the Laser Interferometer Gravitational-wave Observatory (LIGO).
These highly sensitive instruments operate by measuring the phase difference of light along their angled arms,
which changes in response to the minuscule distortions of space-time as gravitational waves pass through.
On 11 February 2016, the LIGO and Virgo Scientific Collaboration announced that they had made the 1st direct observation of gravitational waves.
The observation was made 5 months earlier, on 14 September 2015, by using the Advanced LIGO detectors.
The gravitational waves generated from a pair of merging black holes.
After the initial working, the LIGO instruments detected two more confirmed, and one potential, gravitational wave events.
In August 2017, the two LIGO instruments and the Virgo instrument observed a fourth gravitational wave that merging from black holes,
and a fifth gravitational wave that merge from binary neutron star.
Several other detectors are planned or under construction for the detection of gravitational waves.