While general relativity describes well the behavior of the solar system, Einstein’s theory of gravity and spacetime has not been tested on cosmological scales. Now, a team has analyzed data on 70,000 galaxies to show that the theory is so far the best description of the universe, at least out to 3.5 billion light years from Earth. Specifically, theories without dark matter do not fit the observations.
Galaxy study validates general relativity on cosmic scale, existence of dark matter

Wed, Mar 10, 2010
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