Physicist — Armand Hippolyte Louis Fizeau (Paris 1819 – Venteuil 1896) was a French physicist, famous for his experimental measurements on light. From a well-off family, he was able to devote himself freely to research, collaborating in his youth with Léon Foucault. In 1849 he carried out the first Earth-bound measurement of the speed of light using the toothed-wheel method, obtaining a value very close to the real one without resorting to astronomical observations. In 1851 he performed a famous experiment on the propagation of light in moving water, the results of which would only be explained by Einstein’s relativity. He also studied the Doppler effect as applied to starlight.
Trivia
To measure the speed of light he sent a beam through the teeth of a rapidly spinning wheel, reflected by a mirror over 8 km away: from the rotation speed at which the beam was “blocked” he derived the speed of light.
Theories and contributions
- Measurement of the speed of light (toothed wheel) — First terrestrial method for measuring , yielding a value close to .
- Fizeau experiment — Measurement of the dragging of light by moving water, explained only by special relativity.
- Optical Doppler effect — He independently applied the Doppler effect to light, predicting the shift of spectral lines for moving sources.
Present in chapters
Linked atoms
1 linked atoms.