Einstein was wrong: Wait, no he wasn't… general theory of relativity proved by cosmic experiment

Last week Albert Einstein’s reputation took a glancing blow from CERN scientists who revealed that they may have fired neutrino particles faster than the speed of light.



One of Einstein’s most famous theories – special relativity – states that nothing is capable of doing this.

Now faith has been restored in the legendary thinker by a team of astrophysicists from the Dark Cosmology Centre at the University of Copenhagen, who claim that they’ve proved that another of this theories - general relativity - is absolutely correct.


In this theory, Einstein asserts that gravity is not a force, as such, but an effect produced by the bending of space.

This curving of the universe is caused by the presence of mass, such as a star.

Bright idea: Astrophysicists studied how gravity from distant galaxies affected light - and it did so in exactly the way the Einstein predicted

Einstein claimed that if his thinking was correct then light will be affected by gravity in a certain way – strong gravitational fields should drain some of its energy.


Physicist John Wheeler summed it up like this: ‘Matter tells space-time how to curve, and curved space tells matter how to move.’


Einstein said that light’s energy loss could be measured by studying its wavelengths.
It will be longer in a strong gravity field and shorter in a weak one.

The longer the wavelength, the closer it moves to the red end of the spectrum. This is known in physics as ‘redshifting’.


The University of Copenhagen team, led by Radek Wojtak, set about measuring light emitted from 8,000 galaxy clusters – these are accumulations of thousands of galaxies.


They measured the wavelengths of light emitted from galaxies in the middle of clusters, where gravity is strongest, and from beams emerging from the edges, where it is weakest, because there's less mass.

Their results show that gravity effects light in exactly the way that the theory of relativity predicted.


Mr Wojtak said: ‘We could measure small differences in the redshift of the galaxies and see that the light from galaxies in the middle of a cluster had to “crawl” out through the gravitational field, while it was easier for the light from the outlying galaxies to emerge.’


He then used the general theory of relativity to calculate the gravitational redshift and discovered that Einstein’s thinking was perfectly sound.


Wojtak said: ‘It turned out that the theoretical calculations of the gravitational redshift based on the General Theory of Relativity was in complete agreement with the astronomical observations. Our analysis of observations of galaxy clusters show that the redshift of the light is proportionally offset in relation to the gravitational influence from the galaxy cluster's gravity. In that way our observations confirm the theory of relativity.’


The Dark Cosmology team’s experiment was unique in that gravitational redshift had only been tested in relation to the solar system, not on a cosmological scale.

The results of the study have been published in Nature magazine.