Joseph FourierBirth Chart

Joseph Fourier was a French mathematician and physicist whose work founded central areas of mathematical analysis and the physics of heat. His Théorie analytique de la chaleur (1822) formulated the equation for heat conduction and introduced the method of expansion in trigonometric series—the basis of Fourier analysis and the transform that now bear his name. These ideas transformed the mathematical treatment of thermal diffusion and vibrations.

Over his career, Fourier held prominent academic posts, succeeding Lagrange at the École Polytechnique and later serving as Permanent Secretary of the French Academy of Sciences. He took part in Napoleon’s expedition to Egypt as a scientific advisor and secretary of the Institut d'Égypte, and also contributed to the Description de l'Égypte.

His work made both mathematical contributions—by exploring the representation of functions through series—and physical ones, by systematizing dimensional analysis and proposing the equation for thermal diffusion. Fourier is also associated with the earliest formulation of what is now understood as the greenhouse effect. His legacy endures across multiple branches of science and engineering, and his name is linked to universities, monuments and the inscription of 72 names on the Eiffel Tower.