A boost for science, a wider window to the universe

Subject : Science and technology

Section : Mega science

Concept :

The United States National Science Foundation is partnering with top U.S. universities and India’s Raja Ramanna Centre for Advanced Technology, or RRCAT (a unit of Department of Atomic Energy, Government of India) to launch LIGO-India.

Background

General theory of relativity: Albert Einstein’s 1916 general theory of relativity first predicted the phenomenon of gravitational waves. But it took physicists another century to prove the theory.
Failed to observe: Most of the history of astronomy has been accomplished by observing light and the electromagnetic spectrum, everything from radio waves to infrared and visible light to high-energy x-rays and gamma rays, but gravitational waves are fundamentally different. They are ripples in space-time, the fabric of the universe itself.
First observation: In 2015, for the first time in human history, physicists observed the gravitational waves emanating from two merging black holes, 1.3 million light years from earth.

Laser Interferometer Gravitational-Wave Observatory (LIGO)

LIGO is an international network of laboratories that detect gravitational waves.
LIGOs are designed to measure changes in distance that are several orders of magnitude smaller than the length of the proton. Such high precision Instruments are needed because of the extremely low strength of gravitational waves that make their detection very difficult.

First Detection of Gravitational Waves:

The LIGO in the US first detected gravitational waves in 2015, which led to a Nobel Prize in Physics in 2017.
These gravitational waves were produced by the merger of two black holes, which were about 29 and 36 times the mass of the Sun, 1.3 billion years ago.
Black hole mergers are the source of some of the strongest gravitational waves.
Operational LIGO:
Besides the United States (in Hanford and Livingston), such gravitational wave observatories are currently operational in Italy (Virgo) and Japan (Kagra).Fifth one to be setup in India.
To detect gravitational waves, four comparable detectors need to be operating simultaneously around the globe.
Working Mechanism:
LIGO consists of two 4-km-long vacuum chambers, set up at right angles to each other, with mirrors at the end.
When light rays are released simultaneously in both chambers, they should return at the same time.
However, if a gravitational wave arrives, one chamber gets elongated while the other gets squished, causing a phase difference in the returning light rays.
Detecting this phase difference confirms the presence of a gravitational wave.

LIGO-India Project

The project aims to detect gravitational waves from the
The Indian LIGO would have two perpendicularly placed 4-km long vacuum chambers, that constitute the most sensitive interferometers in the world.
It is expected to begin scientific runs from 2030.
It will be located in the Hingoli district of Maharashtra, about 450 km east of Mumbai.

Purpose and Significance:

It will be the fifth node of the planned network and will bring India into a prestigious international scientific experiment.
It will make India a unique platform that brings together the frontiers of science and technology of the quantum and the cosmos.

Benefits of LIGO-India:

By joining the global network, LIGO-India will push forward the boundaries of what science and technology can achieve and help unlock some of the universe’s greatest mysteries.
The LIGO-India project would have several spin-off benefits to Indian science, apart from making India an integral part of one of the most prestigious international scientific experiments.
The observatory is expected to enable dramatic returns in astronomy and astrophysics, as well as leapfrog Indian science and technology in cutting-edge frontiers of great national relevance.

What are Gravitational Waves?

Gravitational waves were first postulated (1916) in Albert Einstein’s General Theory of Relativity, which explains how gravity works.
These waves are produced by the movement of massive celestial bodies, such as black holes or neutron stars, and are the ripples in spacetime that propagate outward.