Pyotr Nicolayevich Lebedev

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Pyotr Nicolayevich Lebedev

1866-1912

Russian physicist best known for his research into the effects of electromagnetic radiation on matter. Nineteenth-century physicist James Maxwell earlier predicted that electromagnetic waves, such as light, would exert pressure on matter. In 1901 Lebedev designed a refined version of William Crookes's radiometer and successfully measured this light pressure. Lebedev later argued that radiation pressure caused comet tails to point away from the Sun. This effect was later shown to be insignificant compared to that of solar winds.