I recently read Simon Singh’s* fantastic book Fermat’s Last Theorem. Simon is a pro at delivering an absorbing history filled with colorful characters, and in this book one that stood out was Sophie Germain, a French mathematician. In honor of Ada Lovelace Day (already?? It seems to come earlier each year) I figured I’d tell you a little about her.
Sophie was born in Paris on April 1, 1776, a time when women weren’t seen as the mathematical sort. You and I were also born during a time like that, but at least we’d have had a slightly easier time getting into college to study it.
When the French Revolution started heating up, Sophie’s family locked her up in their house to keep her safe, at which point the 13-year old girl took an interest in mathematics. Supposedly, she was inspired by the story of Archimedes, who was so engrossed in a geometry problem he failed to notice that he was about to be murdered by a Roman soldier.
Taking advantage of her father’s extensive library, she taught herself math as well as Greek and Latin so she could study classical scholars. Her parents didn’t like all that book learnin’ (who would marry a girl like that?), so she studied at night until they took away her candles to keep her from reading after dark. She was so committed that eventually her parents gave in, and she became one of the most talented mathematicians in the world.
A man named Monsieur Le Blanc was studying math at the world-famous École Polytechnique, but he ultimately proved to be an uninspired and untalented mathematician. When he left the school for new adventures, Sophie took on his role at the school, using him as a pseudonym to get lecture notes and engage in correspondence with other scholars.
The world’s greatest mathematicians were impressed with M. Le Blanc’s work, and a few of them ended up discovering that Sophie was the real genius behind the name. The most interesting story is Sophie’s relationship with Carl Friedrich Gauss (whose work helped astronomers study Ceres). Gauss and “Le Blanc” had a long and fruitful correspondence, until word reached Sophie that Napoleon was preparing to invade Gauss’ Prussian hometown. Sophie was worried that Gauss would be killed, and so asked a general (who happened to be a family friend) to protect him.
Gauss was spared, and when the general informed him that he owed his life to one Sophie Germain, Abbot-and-Costello-like antics ensued. Eventually, it came out that Sophie was Le Blanc, and Gauss was blown away. He wrote:
But how to describe to you my admiration and astonishment at seeing my esteemed correspondent Monsieur Le Blanc metamorphose himself into this illustrious personage who gives such a brilliant example of what I would find it difficult to believe. A taste for the abstract sciences in general and above all the mysteries of numbers is excessively rare: one is not astonished at it: the enchanting charms of this sublime science reveal only to those who have the courage to go deeply into it. But when a person of the sex which, according to our customs and prejudices, must encounter infinitely more difficulties than men to familiarize herself with these thorny researches, succeeds nevertheless in surmounting these obstacles and penetrating the most obscure parts of them, then without doubt she must have the noblest courage, quite extraordinary talents and superior genius. Indeed nothing could prove to me in so flattering and less equivocal manner that the attractions of this science, which has enriched my life with so many joys, are not chimerical, [than] the predilection with which you have honored it.
Aww. Both mathematicians went on to do more great work. Sophie contributed to the effort to develop a proof for Fermat’s Last Theorem by using prime numbers, discovering (among other things) the importance of prime numbers that fit the equation: if p is a prime number, then 2p+1 is also prime (thanks to Blake for pointing out that I screwed up my math facts!).
Sadly, Gauss fell out of touch with Sophie when he saw something shiny in another field of mathematics. Possibly hoping to make up for his poor correspondence later, he petitioned the University of Göttingen to grant her an honorary degree. Unfortunately, by the time they agreed to give it to her in 1831, Sophie lost a battle with breast cancer.
So there you have it – an awesome lady who fought hard to make great contributions to the world of mathematics. Happy Ada Lovelace Day!