Marina Evseevna Ratner (Russian: Мари́на Евсе́евна Ра́тнер; October 30, 1938 – July 7, 2017[1]) was a professor of mathematics at the University of California, Berkeley who worked in ergodic theory.
[5] Ratner was born in Moscow, Russian SFSR to a Jewish family, where her father was a plant physiologist and her mother a chemist.
Following this, she returned to Moscow State university for graduate studies were under Yakov G. Sinai, also a student of Kolmogorov.
She completed her PhD thesis, titled "Geodesic Flows on Unit Tangent Bundles of Compact Surfaces of Negative Curvature", in 1969.
[8] Her work included proofs of conjectures dealing with unipotent flows on quotients of Lie groups made by S. G. Dani and M. S.