Published in Physics World, 21 Apr 2009
A physicist in the US has calculated that dark matter — the unknown entity that makes up the vast majority of matter in the universe — could arise in a simple generalized quantum theory of gravity.
One of the most enduring problems of modern physics is that the theories of gravity and quantum mechanics do not readily mix. For over 90 years Einstein’s general theory of relativity has done a good job of describing gravity at large lengths scales, but it runs into trouble for all things very small, where quantum mechanics prevails. The trouble is in part due to the fact that quantum mechanics predicts the existence of fleeting “virtual” particles, which in Einstein’s equations cause awkward values of infinity. […]
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