Fizeau Armand Hippolyte Louis (Fizeau Armand-Hippolyte-Louis)

(1819-1896)
Born September 23, 1819 in Paris, professor of family medicine. Dreaming to go in the footsteps of his father, entered the Medical Faculty of the University of Paris. Owing to illness, was forced to interrupt their studies and leave the capital. When he returned to Paris, they have abandoned the study of medicine and decided to study physics. Admitted to the College de France, where a course of lectures known experimental physicist V. Regnault, attended lectures at the Ecole Polytechnique. He studied at the Paris Observatory, led by F. Arago. In 1863 he became a professor at the Ecole Polytechnique in Paris.
The first major achievement in the optics were Fizeau experiments on interference of light using monochromatic radiation. They were delivered to them in 1846 together with Foucault, but the cooperation of scientists did not last long, soon they are separately addressed the problem of measuring the velocity of light in terrestrial conditions. In 1849 Fizeau set has become a classic experience to determine the speed of light using a toothed wheel method (Fizeau). Even before the formulation of this experience, in 1848, Fizeau published theoretical work, in which, regardless of the Doppler formulated the idea of depending on the frequency of light perceived by an observer from the relative motion of the source and the observer. Interest in the optics of moving bodies has led to the formulation Fizeau experiments on the propagation of light in moving water, which confirmed the Fresnel formula. However, the Fizeau believed that despite this assumption, on which the Fresnel formula, may subsequently be revised. Later assumptions Fizeau confirmed: his experiments are now considered as an important confirmation of the relativistic velocity addition rule. Fizeau constructed a number of devices: an induction coil interference spectroscopy, dilatometer, he also studied crystals, doing photography.

In 1875, Fizeau was elected a member of the Royal Society of London, in 1866 awarded the Rumford medal.

Died in Fizeau Nanteye September 18, 1896.