Sophie ’ s Diary

Can a …ctional teenage diary of the mathematician Sophie Germain have dramatic and captivating appeal to audiences ranging from curious teenagers to professional mathematicians? The answer lies in the delicate balance between what we do and don’t know about her real life, along with the extraordinary historical and mathematical circumstances that coalesced with her stranger-than-…ction initiative, perseverance, and mathematical talent, to make her the …rst woman we know to achieve important original mathematical research. In order to understand the full stage setting, let us …rst review what we do know about Sophie Germain, including recent new discoveries about her work, and about Fermat’s Last Theorem, that make her mathematical and personal story both compelling and tantalizing. What we now know leaves both abundant and timely opportunity for the creation of the book under review, a …ctional diary from Sophie Germain age 13 to 17, along with a short non-…ction appendix by the author, Dora Musielak. The real Sophie Germain was born on April 1, 1776 and lived with her parents and sisters in the center of Paris throughout the upheavals of the French Revolution. Even if kept largely indoors, she must as a teenager have heard, and perhaps seen, some of its most dramatic and violent events. Moreover, her father, Ambroise-François Germain, a silk merchant, was an elected member of the third estate to the Constituent Assembly convened in 1789, when the …ctional diary begins [1]. He thus brought home daily intimate knowledge of events in the streets, the courts, etc.; how this was actually shared, feared, and coped with by the real Sophie Germain and her family we do not know. Much of what we know of Germain’s life comes from the biographical obituary [5] published by her friend and fellow mathematician Guglielmo Libri shortly after her death in 1831. He wrote that at age thirteen, Sophie Germain, partly as sustained diversion from her fears of the Revolution