Algebra is nothing but written geometry; geometry is nothing but drawn algebra.

— Sophie Germain, General Considerations on the State of the Sciences and Letters (1833)

Sophie Germain (1776–1831) was never allowed into a university, because she was a woman. She taught herself mathematics by candlelight, against her parents’ wishes. To be read by Lagrange and Gauss, the two greatest mathematicians of the day, she hid behind a man’s name, Monsieur Le Blanc. Even so, she made the biggest advance in more than a century on Fermat’s Last Theorem, and she was the first woman to win a major prize of the Paris Academy of Sciences, with a theory of vibrating plates.

In this trail we tell Sophie Germain’s life and redo, with the calculations in full, six of the subjects she worked on: the congruences she learned from Gauss, her theorem on Fermat, the primes that bear her name, an algebraic identity, Chladni’s sand figures and mean curvature.

Sophie Germain

Who she was

Sophie Germain

Nascimento
1 April 1776, Paris
Morte
27 June 1831, Paris
Origem
France
Áreas
Number theory, elasticity and philosophy

Reading guide

Biography

Discovery and proof

Legacy and sources