Hertz, Heinrich Rudolf

Hertz, Heinrich Rudolf (Ger. hīn`rĭkh r`dôlf hĕrts), 1857–94, German physicist. He confirmed J. C. Maxwell's electromagnetic theory and in the course of experiments (1886–89) produced and studied electromagnetic waves (known also as hertzian waves, or radio waves). He demonstrated that these are long, transverse waves that travel at the velocity of light and can be reflected, refracted, and polarized like light. Hertz also investigated electric discharge in rarefied gases. The unit of frequency called hertz was named in his honor. His writings include Electric Waves (1890, tr. 1893) and Principles of Mechanics (1894, tr. 1899).