Maryam Mirzakhani, the world's first female Fields Medal winner and Persia's first winner of that award, died of breast cancer at an American hospital [on July 15, 2017]. . . .
Her medal was mostly for her work on the moduli spaces of Riemann surfaces, especially for her 2007 proof of a formula for volumes of the moduli spaces (previously conjectured by Witten, Kontsevich, guys of this caliber are normal in that field). However, she has done lots of related mathematical work that was usually focusing on the modular group, moduli spaces, and geodesics – which were sometimes shown to be ergodic, sometimes very regular and not chaotic, and similar issues were relevant.
- An obituary post from an acquaintance of her and her Czech husband who survives her is here.