Sophie Germain

1776-1831

French Mathematician

Among the achievements of Sophie Germain's career was her attempt at a proof of Fermat's Last Theorem. Her successes were all the more remarkable in light of the fact that she was largely self-taught and practiced at the fringes of a mathematical establishment largely closed to women at that time.

She was born Marie-Sophie Germain, the middle child of Ambroise-François and Marie-Madeleine Germain, in Paris on April 1, 1776. Later, she would drop the "Marie" because both her mother and her older sister also bore that name in hyphenated form.

In time, both of her sisters would marry successful men, but Sophie's own future—which held neither marriage nor children—was influenced by events that took place when she was 13 years old. That year was when the French Revolution began, and, although her father served in the revolutionary legislative assembly, the tumultuous events of 1789 took their toll on Sophie. She quite literally hid in the family library, where, for the next six years, she undertook a campaign of self-education that would have been impressive even under conditions of peace. Not only did she teach herself Latin and Greek but she also managed to learn algebra, geometry, and calculus.

Germain's formal education was slight but she submitted papers—under the pseudonym Monsieur Le Blanc (Mr. White)—for a course taught by Joseph-Louis Lagrange (1736-1813) at the Ecole Polytechnique. So great was Lagrange's respect for the work of "le Blanc" that he sought out the mystery man and, when he discovered that le Blanc was a woman, he extolled her abilities.

Lagrange was but one of many distinguished mathematicians who, to one degree or another, took Germain under their wings. She carried on a lengthy correspondence with Carl Friedrich Gauss (1777-1855) and in 1806 used her family's political connections to help protect the German mathematician from Napoleonic soldiers invading his homeland. Germain was also acquainted with Augustin-Louis Cauchy (1789-1857) and Jean-Baptiste-Joseph Fourier (1769-1830).

Her correspondence with Adrien-Marie Legendre (1752-1833) led to a collaboration of sorts, and Legendre in 1830 published Germain's proof of Fermat's Last Theorem in Théorie des nombres. The proof, like all attempts through the early 1990s, turned out to be incorrect, but Germain nonetheless advanced the understanding of the problem.

Between 1811 and 1815, Germain was the sole contender in three contests sponsored by the Institut de France, which challenged contestants to "formulate a mathematical theory of elastic surfaces and indicate just how it agrees with empirical evidence." Germain's first two solutions were rejected but, although the third had some questionable aspects, it nonetheless won the prize.

Germain became the first woman not married to a member of the Académie des Sciences to attend its meetings, a measure of the respect that her efforts had gained for her. She died of breast cancer in Paris on June 27, 1831.

JUDSON KNIGHT