Watch these videos if you aren't sure what gravitational waves are (and why India is studying them)

Soon after gravitational waves were first detected in February, the Indian government gave their in-principle nod to opening a laboratory in India, the third such facility in the world. More recently, the government announced that Hingoli district in Maharashtra could be the site of the ambitious Laser Interferometer Gravitational-Wave Observatory or LIGO project. It is scheduled to be operational by 2024 and will be the first such facility outside the United States.

The video above is a short guide to gravitational waves and what they exactly are: "It started in 1915 with Einstein. He hypothesised that all objects with mass would warp the fabric of space time. If the mass was great enough, those distortions could cause other objects to fall into them. Einstein also predicted that these distortions could travel across the universe stretching and squeezing space and time as they moved and this is what we call gravitational waves."

The video below explains the LIGO project. "To measure this stretching and squeezing, a device called an interferometer is used. A laser beam is split and sent through two long perpendicular tubes, each precisely the same lengths. The two beams bounce of mirrors and recombine back at the base." While normal waves cancel each other out, gravitational waves behave unpredictably and alter their environment. Each LIGO lab is a real life visualisation of this experiment and has two arms extending four kilometres in length.

Here's one from the Massachusetts Institute of Technology made when the gravitational waves were first detected where scientists talk about the importance of the discovery and compare it to Galileo Galilei discovery's. One of them says, "I would love to say Einstein's face as he reads the article we just put out. He would be as dumbfounded as we are."