On February 11, scientists made one of the most stunning scientific announcements of the past century. For the first time in history, instruments have detected gravitational waves.
A hundred years ago, physicist Albert Einstein proposed his general theory of relativity. GR theorizes that gravity is a property of space and time. Energy and mass cause spacetime to distort and curve. Curved spacetime causes matter to move.
As a pictorial example, imagine a flat sheet of material with a marble sitting on it. If you push your finger down in the middle of the material, it will create a dimple. The marble will then roll into the dimple. In the same way, a dimple in spacetime created by the Sun causes the gravitational force that holds the Earth in its orbit.
GR led to the prediction of black holes. These are regions of space where spacetime becomes so distorted that even light cannot escape. GR also implied the existence of gravitational waves. These are “ripples” in spacetime that emanate outward from a gravitational event, as if a pebble were dropped in water.
Keep in mind, all of this was only theoretical. For decades, scientists searched for actual proof of gravitational waves.
Finally, on September 15, 2015 the Advanced Laser Interferometer Gravitational-Wave Observatory (LIGO) observed the gravitational waves created by the collision of two black holes more than one billion light-years away from Earth. The oscillation (which increased in frequency as the black holes spiraled into each other) ran from 35 Hz to 260 Hz and lasted only a quarter of a second. Scientists spent several months confirming that there was no error or other possible explanation before finally announcing the news.
“The discovery is significant for two reasons,” says Agilent’s Jim Hollenhorst. “First, it is the most direct observation showing that Einstein’s theory works in the most extreme conditions of curved spacetime. Second, it opens up a new window for observational astronomy. Whenever this has happened before – as with radio and X-ray astronomy – we’ve seen amazing things that no one had previously imagined.”
Agilent (as Varian) provides a significant amount of vacuum equipment to the LIGO facilities. Equipment includes specially built ion pumps, which are used for electron device and detector applications.
“As the most sensitive instrument in the world, LIGO is an inspiration to Agilent scientists and engineers in their quest to measure with ever greater precision,” Jim says.
For more information go to: