LIGO makes gravitational wave announcement today

Following weeks of rumours that gravitational waves have finally been discovered, scientists are set to make an announcement Thursday morning.

Scientists with the U.S.-based Laser Interferometer Gravitational-Wave Observatory, which includes some Canadians, will provide an update on the search for gravitational waves at 10:30 a.m. Thursday, LIGO announced earlier this week. The event will be webcast live from the National Press Club in Washington, D.C.

Gravitational waves are ripples in space-time that Albert Einstein's theory of general relativity predicted would be produced by massive phenomena such as neutron stars or black holes colliding.

Such events don't normally give off light and can't be detected using normal telescopes, so observing their gravitational waves would allow scientists to study things that have never been seen before. It would also tell physicists whether Einstein's general theory of relativity is really correct.

The theory turned 100 years old this year. And despite decades of searching, gravitational waves have not yet been officially detected.

But rumours have been heating up that LIGO has finally seen something. Twitter posts about that from Arizona State University theoretical physicist Lawrence Krauss, who is not part of the LIGO collaboration, caused a huge buzz on the internet in January. Since then, many people have been waiting for an official announcement from LIGO.

The Canadian Institute for Theoretical Physics at the University of Toronto helped make the software used to analyze the data and look for gravity waves.

The experiment aims to detect gravitational waves by measuring their effect using two L-shaped detectors about 3,200 kilometres apart. Passing gravitational waves are expected to make light take slightly longer to travel in one direction than the other. To us, that make it looks like a decrease in the length of one arm of the L and an increase in the other. The minuscule change is measured using lasers and mirrors. A real gravitational wave should be detected by both detectors.