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The newly developed theory of emergent gravity, proposed as an alternative to dark matter, struggles in one of its first trials.
The physicist who designed the LIGO experiment that detected gravitational waves still holes up in a small basement lab surrounded by electronics and optical instruments.
Does the force of gravity change at large scales? Perhaps not, but a new theory of dark matter shows why that could appear to be the case.
A series of observations at the very edge of the universe has reignited a debate over what lifted the primordial cosmic fog.