Biography of Sophie Germain, Mathematical Pioneer Woman

Sophie Germaine dedicated herself early to becoming a mathematician, despite family obstacles and lack of precedent. The French Academy of Sciences awarded her a prize for a paper on the patterns produced by vibration. This work was foundational to the applied mathematics used in the construction of skyscrapers today, and was important at the time to the new field of mathematical physics, especially to the study of acoustics and elasticity.

Early Life

Sophie Germain's father was Ambroise-Francois Germain, a wealthy middle-class silk merchant, and a French politician who served in the Estates Général and later in the Constituent Assembly. He later became a director of the Bank of France. Her mother was Marie-Madeleine Gruguelu, and her sisters, one older and one younger, were named Marie-Madeleine and Angelique-Ambroise. She was known simply as Sophie to avoid confusion with all the Maries in the household.

When Sophie Germain was 13, her parents kept her isolated from the turmoil of the French Revolution by keeping her in the house. She fought boredom by reading from her father's extensive library. She may also have had private tutors during this time.

Discovering Mathematics

A story told of those years is that Sophie Germain read the story of Archimedes of Syracuse who was reading geometry as he was killed — and she decided to commit her life to a subject that could so absorb one's attention.

After discovering geometry, Sophie Germain taught herself mathematics, and also Latin and Greek so that she could read the classical mathematics texts. Her parents opposed her study and tried to stop it, so she studied at night. They took away candles and forbid nighttime fires, even taking her clothes away, all so that she could not read at night. Her response: she smuggled candles, she wrapped herself in her bedclothes. She still found ways to study. Finally, the family gave in to her mathematical study.

University Study

In the eighteenth century in France, a woman was not normally accepted in universities. But the École Polytechnique, where exciting research on mathematics was happening, allowed Sophie Germain to borrow the lecture notes of the university's professors. She followed a common practice of sending comments to professors, sometimes including original notes on mathematics problems as well. But unlike male students, she used a pseudonym, "M. le Blanc" — hiding behind a male pseudonym as many women have done to have their ideas taken seriously.

Blazing a Trail in Mathematics

Beginning this way, Sophie Germain corresponded with many mathematicians and "M. le Blanc" began to have an impact in turn on them. Two of these mathematicians stand out: Joseph-Louis Lagrange, who soon discovered that "le Blanc" was a woman and continued the correspondence anyway, and Carl Friedrich Gauss of Germany, who eventually also discovered that he'd been exchanging ideas with a woman for three years.

Before 1808 Germain mainly worked in number theory. Then she became interested in Chladni figures, patterns produced by vibration. She anonymously entered a paper on the problem into a contest sponsored by the French Academy of Sciences in 1811, and it was the only such paper submitted. The judges found errors, extended the deadline, and she was finally awarded the prize on January 8, 1816. She did not attend the ceremony, though, for fear of the scandal that might result.

This work was foundational to the applied mathematics used in construction of skyscrapers today, and was important at the time to the new field of mathematical physics, especially to the study of acoustics and elasticity.

In her work on number theory, Sophie Germain made partial progress on a proof of Fermat's Last Theorem. For prime exponents less than 100, she showed there could be no solutions relatively prime to the exponent.

Acceptance

Accepted now into the community of scientists, Sophie Germain was allowed to attend sessions at the Institut de France, the first woman with this privilege. She continued her solo work and her correspondence until she died in 1831 of breast cancer.

Carl Friedrich Gauss had lobbied to have an honorary doctorate awarded to Sophie Germain by Göttingen University, but she died before it could be awarded.

Legacy

A school in Paris — L'École Sophie Germain — and a street — la rue Germain — honor her memory in Paris today. Certain prime numbers are called "Sophie Germain primes."

Sources

• Bucciarelli, Louis L., and Nancy Dworsky. Sophie Germain: An Essay in the History of the Theory of Elasticity. 1980.
• Dalmédico, Amy D. "Sophie Germain," Scientific American 265: 116-122. 1991.
• Laubenbacher, Reinhard and David Pengelley. Mathematical Expeditions: Chronicles by the Explorers. 1998.
  Sophie Germain's story is told as part of the story of Fermat's Last Theorem, one of five major themes in this volume
• Osen, Lynn M. Women in Mathematics. 1975.
• Perl, Teri, and Analee Nunan. Women and Numbers: Lives of Women Mathematicians Plus Discovery Activities. 1993.