Tidal forces carry the mathematical signature of gravitational waves - MIT Technology Review

The idea is something of a technicality, but nevertheless an interesting one.

“... use some mathematical wizardry to show that tidal forces are gravitational waves. These are the same forces that cause sea levels to rise and fall as the moon moves around the Earth. “Tidal forces are actually a hidden form of gravitational waves,” they say.

First some background. Newton’s theory of gravity is based on the idea that all masses generate an attractive gravitational force explaining a wide variety of phenomena: the trajectory of a falling apple, the motion of the planets around the sun, and so on.

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