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Scientists report the possible discovery of primordial gravitational waves, ripples in space-time that carry a record of how the universe began.
New calculations suggest physicists may someday discover a fundamental theory of gravity, but it could require a radical new perspective on the universe.
Physicists have devised experiments that can probe the interface between quantum mechanics and general relativity.
Physicists have discovered a jewel-shaped geometric object that challenges the notion that space and time are fundamental constituents of nature.
New findings suggest that beneath the surface of quantum theory lies a vibrant string theory world where some matter corresponds to black holes in higher dimensions.
If a new hypothesis about black hole firewalls proves correct, at least one of three cherished notions in theoretical physics must be wrong.