ABCs of gravitational waves

NASA researchers simulated the gravitational waves that would be produced when two black holes merged. [Photo/NASA]

Why is the discovery so significant?

While opening a door to new ways to observe the universe, scientists said gravitational waves should help them gain knowledge about enigmatic objects like black holes and neutron stars. The waves also may provide insight into the mysterious nature of the very early universe.

The scientists said that because gravitational waves are so radically different from electromagnetic waves they expect them to reveal big surprises about the universe.

Everything we knew until now about the cosmos stemmed from electromagnetic waves such as radio waves, visible light, infrared light, X-rays and gamma rays. Because such waves encounter interference as they travel across the universe, they can tell only part of the story.

Gravitational waves experience no such barriers, meaning they offer a wealth of additional information. Black holes, for example, do not emit light, radio waves and the like, but can be studied via gravitational waves.

Einstein in 1916 proposed the existence of gravitational waves as an outgrowth of his ground-breaking general theory of relativity, which depicted gravity as a distortion of space and time triggered by the presence of matter. Until now scientists had found only indirect evidence of their existence, beginning in the 1970s.