Asked by: Keith Mayes, Norfolk
Einstein’s theory of gravity predicts that the Universe began in a singularity – a state of zero size and thus infinite density and gravitational force, which would prevent it expanding.
But theorists believe that such a state – also predicted to exist inside black holes – is the result of his celebrated theory ignoring quantum effects. These would prevent a truly point-like singularity from forming, eliminating the infinitely strong gravity, and thus allowing the Universe to expand.
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