Physics is supposed to be predictable. Drop a ball, and gravity pulls it down. Heat water, and it boils. Light travels in straight lines. Yet throughout history, scientists have encountered ...

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There are precision measurements, and then there’s the Laser Interferometer Gravitational-Wave Observatory. In each of LIGO’s twin gravitational wave detectors (one in Hanford, Washington, and the ...

Just over a week ago, European physicists announced they had measured the strength of gravity on the smallest scale ever. In a clever tabletop experiment, researchers at Leiden University in the ...