An experiment published in the journal Science shows that Einstein’s theory of general relativity works on a huge scale. Astronomers used a galaxy to see if the theory works on a larger scale.
Somehow, scientists hoped that if the results failed, they might have gotten some more information on the Universe’s mysteries. However, the theory of general relativity was proven to be right!
Astronomers used data from the Very Large Telescope at the European Southern Observatory and data from NASA’s Hubble Space Telescope. They looked at how light was curved by a close galaxy, according to the explanation of gravity proposed by Einstein.
Back in 1915, Sir Arthur Eddington tested the theory on a smaller scale, looking at the time of starlight as it appeared from the Sun which was eclipsed. He saw that its mass bent the pathway. After the results, Albert Einstein’s concept of general relativity became part of physics books.
Ever since Sir Arthur Eddington’s tests, the mathematics behind the dent made in the fabric of space-time by massive bodies was only tested on stars. Now, scientists wanted to see if the concept works at a bigger scale, and although they were all expecting to work, some physicists hoped that they could prove Einstein was wrong. In science, it’s the next best thing (- after produced that he’s right).
Testing General Relativity on a Galaxy
Astronomer Thomas Collett (the University of Portsmouth) said that “general relativity predicts that massive objects deform space-time. This means that when light passes near another galaxy, the light’s path is deflected.”
But so far, nobody measured to see the curvature produce by whole galaxies. The team looked at the galaxy called E325 (short for ESO325-G004), which is 500 million light-years away – pretty close, in cosmic terms.
The E325 eclipsed a second galaxy, making the background light follow a path created by E325’s bulk. Astronomers measure the speed of the stars in the E325 to estimate its mass, explains Collett:
“We then compared this mass to the strong lensing image separations that we observed with the Hubble Space Telescope. This is the most precise extrasolar test of general relativity to date, from just one galaxy.”
Andre Blair s is the lead editor for Advocator.ca. He holds a B.A. in Psychology from the University of Toronto, and a Master of Science in Public Health (M.S.P.H.) from the School of Public Health, Department of Health Administration, at the University of North Carolina at Chapel Hill. Andre specializes in environmental health, but writes on a variety of issues.