Scientists Finally Calculated The Speed of Gravity
Scientists Finally Calculated The Speed of Gravity
In classical theories of gravitation, the changes in a gravitational field propagate. A change in the distribution of energy and momentum of matter results in subsequent alteration, at a distance, of the gravitational field which it produces. In the relativistic sense, the « speed of gravity » refers to the speed of a gravitational wave, which, as predicted by general relativity and confirmed by observation of the GW170817 neutron star merger, is the same speed as the speed of light
Learn more : https://en.wikipedia.org/wiki/Speed_of_gravity
Recently, scientists made groundbreaking detections that allowed them that gravity does not act instantaneously as Newton thought, instead it propagates at the speed of light.
“The speed of gravity, like the speed of light, is one of the fundamental constants in the Universe. Until the advent of gravitational wave astronomy, we had no way to directly measure the speed of gravity.” ( Neil Cornish, a physicist at Montana State University )
Scientists captured the neutron star while emitting gravitational waves and electromagnetic radiation as well from the gamma rays. The simultaneous emission of both gravitational waves and light from the same origin enabled scientists to set limits on the speed of gravity that is many requests of extent more stringent than what could be set utilizing gravitational wave flags alone.
When a source emits both gravitational waves and light, scientists can measure the difference (if any) in the arrival times of the two different types of signals at a single detector.
Later on, scientists compared signals detected by two LIGO detectors located 1800 miles apart: one in Hanford, Washington, and the other in Livingston, Louisiana.
Scientists noted, “it’s possible to greatly improve the bounds on the speed of gravity using sources that emit only gravitational waves. The constraints could improve to within 1% of the speed of light
Cornish said, “Many alternative theories of gravity, including some that have been invoked to explain the accelerated expansion of the Universe, predict that the speed of gravity is different from the speed of light. Several of those theories have now been ruled out, thereby restricting the ways in which Einstein’s theory can sensibly be modified, and making dark energy a more likely explanation for the accelerated expansion.”
In this video I show you what the speed of gravity is and then show you what happens if the sun suddenly disappeared. What would happen to the orbits of the planets? Then I talk about why some people say that gravity is instantaneous and some say it is not. The software I used in the video is called Universe Sandbox 2.
