Everything about: Gravitational Waves

Gravitational Waves (GW):

• When 2 black holes merge, it will radiate GW. GW are ‘ripples’ in the fabric of space-time caused by some of the most violent and energetic processes in the Universe.
• They are extremely weak so are very difficult to detect.
• Albert Einstein predicted the existence of gravitational waves in 1916 in his general theory of relativity.
• These ripples travel at the speed of light without being scattered significantly.

Sources of Gravitational waves

• Mergers of black holes or neutron stars, rapidly rotating neutron stars, supernova explosions and the remnants of the disturbance caused by the formation of the universe, the Big Bang itself, are the strongest sources.
• There can be many other sources, but these are likely to be too weak to detect.

Interferometer

• It is an instrument that uses interference patterns formed by waves (usually light, radio, or sound waves) to measure certain characteristics of the waves themselves or of materials that reflect, refract, or transmit the waves.
• Interferometers can also be used to make precise measurements of distance.
• Interference patterns are produced when two identical series of waves are brought together.

Laser Interferometer Gravitational Wave Observatory (LIGO)

• It is the world's largest gravitational wave observatory and a wonder of precision engineering.
• It comprises of two enormous laser interferometers located thousands of kilometres apart, each having two arms which are 4 km long. The detectors are in (Livingston) Louisiana and (Hanford) Washington.
• It exploits the physical properties of light and of space itself to detect and understand the origins of Gravitational Waves (GW). Upgraded version is called Advanced LIGO.
• The Japanese detector, KAGRA, or Kamioka Gravitational-wave Detector, is expected to join the international network soon.
• LIGO detectors: Unlike optical or radio telescopes, it does not see electromagnetic radiation

IndIGO (India Initiative of GW Observations) in Hingoli district, Maharashtra.

• The proposed LIGO-India project aims to move one Advanced LIGO detector from Hanford to India.
• LIGO-India project is envisaged as an international collaboration between the LIGO Laboratory and 3 lead institutions in the IndIGO consortium: Institute of Plasma Research (IPR) Gandhinagar, Inter University Centre for Astronomy and Astrophysics (IUCAA), Pune and Raja Ramanna Centre for Advanced Technology (RRCAT), Indore.

Significance of IndiGo Project

• To locate the source of gravitational waves more accurately.
• Identification of new sources.
• The project will help Indian scientific community to be a major player in the emerging research frontier of GW astronomy.
• The high-end engineering requirements of the project (such as the world's largest ultra-high vacuum facility) will provide unprecedented opportunities for Indian industries in collaboration with academic research institutions.
• A cutting edge project in India can serve as a local focus to interest and inspire students and young scientists.