After 87 years, Einstein proved right on speed of gravity
Agence France-Presse
Paris, January 9
http://www.hindustantimes.com/news/181_134719,00040001.htm
More than 87 years after it was devised, a theory by Albert Einstein that gravitational force moves at the speed of light has finally been confirmed by a pair of US-based scientists.
The assumption that gravity travels at light speed is central to Einstein's construction of space-time, the general theory of relativity, which he devised in 1915 but which has never been tested.
In the absence of any confirmation, interest has flourished in a novel theory called "brane worlds" that suggests there are other dimensions to ordinary matter.
Gravity can take a short-cut through these extra dimensions, while light is confined to the world of ordinary matter, which is known as the "main brane," according to this theory.
In this way, gravitational waves could appear to travel faster than the speed of light in our world, yet not violate Einstein's sacred equations about general relativity.
Ed Fomalont, a scientist at the US National Radio Astronomy Observatory in Charlottesville, Virginia, and Sergei Kopeikin, a professor of theoretical physics at the University of Missouri-Columbia, have now ridden to Einstein's rescue.
In an unprecedented operation that unfolded last September, they measured light from a powerful distant source, a quasar, as Jupiter passed by.
As the wave of light came close to Jupiter, it was deflected by the giant planet's massive gravitational force before emerging again and continuing on to Earth.
Agence France-Presse
Paris, January 9
http://www.hindustantimes.com/news/181_134719,00040001.htm
More than 87 years after it was devised, a theory by Albert Einstein that gravitational force moves at the speed of light has finally been confirmed by a pair of US-based scientists.
The assumption that gravity travels at light speed is central to Einstein's construction of space-time, the general theory of relativity, which he devised in 1915 but which has never been tested.
In the absence of any confirmation, interest has flourished in a novel theory called "brane worlds" that suggests there are other dimensions to ordinary matter.
Gravity can take a short-cut through these extra dimensions, while light is confined to the world of ordinary matter, which is known as the "main brane," according to this theory.
In this way, gravitational waves could appear to travel faster than the speed of light in our world, yet not violate Einstein's sacred equations about general relativity.
Ed Fomalont, a scientist at the US National Radio Astronomy Observatory in Charlottesville, Virginia, and Sergei Kopeikin, a professor of theoretical physics at the University of Missouri-Columbia, have now ridden to Einstein's rescue.
In an unprecedented operation that unfolded last September, they measured light from a powerful distant source, a quasar, as Jupiter passed by.
As the wave of light came close to Jupiter, it was deflected by the giant planet's massive gravitational force before emerging again and continuing on to Earth.