Gravitational Waves Current Affairs - 2019

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Union Cabinet gives nod to LIGO-India mega science proposal

The Union Cabinet has approved the LIGO-India project (Laser Interferometer Gravitational-wave Observatory in India) proposal for research on gravitational waves.

The approval coincides with the historic first time detection of gravitational waves that had opened up of a new window on the universe to unravel some of its greatest mysteries.

Key facts

  • LIGO-India project is piloted by Department of Atomic Energy (DAE) and Department of Science and Technology (DST). It will give impetus to scientific research in the country.
  • It will establish a state-of-the-art Gravitational Wave Observatory in India in collaboration with the US based LIGO Laboratory run by Caltech and MIT.
  • The project will help Indian scientists and engineers to take global leadership in this new astronomical frontier by doing research into the realm of gravitational wave.
  • It will also bring considerable opportunities in cutting edge technology in India’s scientific industry as domestic players will engaged in the construction of 8 kilometre long beam tube at ultra-high vacuum of observatory on a levelled terrain.

Background

  • The proposal for LIGO-India project was made under the India-United States cooperation agreement US LIGO lab and US National Science Foundation (NSF) in October 2011 for locating an interferometer in India.
  • Formal proposal in this regard was submitted to the DAE and DST by the Indian Initiative in Gravitational-wave Observations (IndiGO) Consortium (formed in 2009).
  • Under this proposal, US was going to provide all the hardware and technology required for project and India’s responsibility will be to construct and operate it.

For first time Scientists discover Gravitational Waves

Scientist for the first time have discovered Gravitational Waves (GW) that were hypothesised by Albert Einstein in 1916.

These waves were detected by the scientists working at two LIGO (Laser Interferometer Gravitational-wave Observatory) facilities in United States.

Key facts

  • LIGO scientists have detected these gravitational waves produced by collision of two black holes located 1.3 billion light years away from earth.
  • Process of Discovery: The LIGO experiment has 4km long L-shaped tunnels and uses lasers to measures changes in the distance between two ends.
  • When the GW enters into LIGO, it stretches space and direction, and disperses space in another direction i.e. these waves disturb the light emitted lasers.
  • Scientists by measuring the interference (disturbances) of lasers light map the disturbed space which has been compressed or stretched.

What are Gravitational Waves?

  • In physics, gravitational waves are ripples in the curvature of spacetime which propagate as waves, travelling outward from the source at the speed of light.
  • Predicted in 1916 by Albert Einstein on the basis of his Theory of General Relativity.
  • Gravitational waves transport energy as gravitational radiation and pass through matter without interacting with it.

Previous evidences: Earlier in 1974, Russel Hulse and Joseph Taylor had disovered indirect evidence for the existence of gravitational waves emitted from the decaying orbital period of objects called binary pulsars. Both of them for their discovery were awarded the Nobel Prize in Physics in 1993.

Significance

  • This discovery opens new window in studying cosmos and unlock secrets about the early universe and mysterious objects like black holes and neutron stars.
  • Confirms a key prediction of Albert Einstein’s General Theory of Relativity.
  • Gravitational waves may be useful for studying black holes and other dark objects.
  • As these waves do not interact with matter, gravitational waves coming to Earth may be carrying undistorted information about its origin.
  • It may also improve methods for estimating the distances to other galaxies. It may also help in mapping the abundance of black holes and frequency of their mergers.