Jean-Baptiste Joseph Fourier

1768-1830

French Mathematician, Egyptologist and Administrator

Jean-Baptiste Joseph Fourier was a French mathematician, Egyptologist, and administrator with the French government. He is best remembered for his work on the analysis of functions in terms of a type of infinite mathematical series now known as Fourier series. This type of analysis has many important applications in the physical sciences.

Fourier was born on March 21, 1768, in Auxerre, France, the ninth child of a tailor and his second wife. Both his parents were dead by the time he was 10, and he was sent to a local military school run by Benedictine monks. He exhibited a great proficiency in mathematics, and eventually became a teacher there.

Fourier considered training for the priesthood, but became embroiled in politics in the wake of the French Revolution. He joined the local Revolutionary Committee, and became enamored of "the sublime hope of establishing among us a free government exempt from kings and priests." Although he deplored the subsequent Reign of Terror and tried, unsuccessfully, to resign from the committee in protest, he was at this point hopelessly entangled. As various factions rose and fell, fortunes changed. Fourier was twice jailed, fearing the guillotine. Each time, fortunately, he was released. Between prison stays, Fourier was associated with newly founded schools in Paris, the Ecole Normale and the Ecole Polytechnique.

In 1798, Fourier joined Napoleon on his expedition to Egypt. For three years, he conducted research on Egyptian antiquities, consulted on engineering projects and diplomatic undertakings, and served as the secretary of the Institut d'Egypte. After his return to France, he was responsible for publishing the massive body of scientific and literary discoveries from Egypt, a project that became the Description d'Egypte. This work includes Fourier's significant historical preface on Egypt's ancient civilization.

Between 1802 and 1814, Fourier was based in Grenoble as prefect for the French region or departement, of Isère. While supervising such official projects as the draining of swamps, he also continued his work in mathematics and Egyptology. Napoleon rewarded him in 1809 with the title of baron, but fell from power in 1815. This resulted in Fourier being transferred to head the Statistical Bureau of the Seine, allowing him to resume his academic life in the city of Paris. He was elected to the Académie des Sciences in 1817, and the Académie Française in 1826.

Fourier series arose from work that the mathematician began in Grenoble and finished in Paris in 1822. In his Théorie analytique de la chaleur ("Analytical Theory of Heat"), Fourier showed how the conduction of heat in solid bodies could be analyzed in terms of series with sines and cosines as terms. The implications of this method were much wider-ranging than heat conduction, affecting data analysis techniques in many scientific and engineering fields. It also had a great influence on the theory of functions of a real variable.

During his last years, Fourier published a number of papers in both pure and applied mathematics. He died in Paris on May 16, 1830.

SHERRI CHASIN CALVO