Einstein's general theory of relativity came under attack last month when physicists reported making neutrinos travel faster than light.

Einstein's theory of relativity encompasses two theories - special and general. Special relativity, which deals with space-time, is now being reviewed by CERN scientists. The general theory of relativity of late, however, gained more importance with the astrophysicists who proved that Einstein's theory is still correct on the cosmic scale.

According to the general theory of relativity, the gravity of any particle affects space-time deeply by warping it. The theory was validated previously by studying the sun and other stars.

Should CERN's findings turn out be true, they would violate Einstein's theory of relativity, opening it to rigorous scientific evaluation.

A neutrino is one of the particles that according to the theory of physics called the standard model is elementary, that is, fundamental. Neutrinos are produced naturally in radioactive decays in the sun and by cosmic rays. They can also be produced in reactors and accelerators.

All these developments have resulted in the need for further validation of the theory by Einstein. A team of Danish astrophysicists has claimed to have validated Einstein's theory by studying the cosmos. The finding was published in Nature.

A team of astrophysicists from the Niels Bohr Institute, led by Radek Wojtak, collected data from about 8,000 galaxy clusters by the Sloan Digital Sky Survey and performed a statistical analysis. The goal of the work was to detect gravitational red shift by studying the properties of the red-shift distribution of galaxies in clusters rather than by looking at red shifts of individual galaxies separately, Wojtak explains.

Their research on galaxy clusters clearly shows that the red shift of the light is proportionally offset in relation to the gravitational influence from the galaxy cluster's gravity, says Wojtak. In that way our observations confirm the theory of relativity.

In yet another development, scientists say that Einstein's general theory of relativity posits that a slight difference in the force of gravity at two different places causes clocks in those places to tick at different rates. Carlo Contaldi, a theoretical physicist at the Imperial College London, as reported by Livescience.com, has argued that when physicists recently measured neutrinos traveling at 1.000025 times the light-speed between Switzerland and Italy, they didn't fully correct for this effect, and that failing to do so could have caused their shocking results.

All these point to the need for further tests before these results are fully confirmed and widely accepted. At the moment it can be said that if neutrinos do travel faster than the speed of light it would be a revolutionary discovery.

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