Maryna Sergiivna Viazovska (, ; born 2 December 1984) is a Ukrainian mathematician known for her work in sphere packing. She is full professor and Chair of Number Theory at the Institute of Mathematics of the École Polytechnique Fédérale de Lausanne in Switzerland. She was awarded the Fields Medal in 2022. Education and career Viazovska was born in Kyiv, the oldest of three sisters. Her father was a chemist who worked at the Antonov aircraft factory and her mother an engineer. She attended a specialized secondary school for high-achieving students in science and technology, Kyiv Natural Science Lyceum No. 145. An influential teacher there, Andrii Knyazyuk, had previously worked as a professional research mathematician before becoming a secondary school teacher. Viazovska competed in domestic mathematics Olympiads when she was at high school, placing 13th in a national competition where 12 students were selected to a training camp before a six-member team for the International Mathematical Olympiad was chosen. As a student at Taras Shevchenko National University of Kyiv, she competed at the International Mathematics Competition for University Students in 2002, 2003, 2004, and 2005, and was one of the first-place winners in 2002 and 2005. She co-authored her first research paper in 2005. Viazovska earned a master's from the University of Kaiserslautern in 2007, PhD from the Institute of Mathematics of the National Academy of Sciences of Ukraine in 2010, and a doctorate (Dr. rer. nat.) from the University of Bonn in 2013. Her doctoral dissertation, Modular Functions and Special Cycles, concerns analytic number theory and was supervised by Don Zagier and Werner Müller. She was a postdoctoral researcher at the Berlin Mathematical School and the Humboldt University of Berlin and a Minerva Distinguished Visitor at Princeton University. Since January 2018 she has held the Chair of Number Theory as a full professor at the École Polytechnique Fédérale de Lausanne (EPFL) in Switzerland after a short stint as tenure-track assistant professor. Contributions In 2016, Viazovska solved the sphere-packing problem in dimension 8. Her dimension 8 solution quickly led to collaboration with others, and a solution in dimension 24. Previously, the problem had been solved only for three or fewer dimensions, and the proof of the three-dimensional version (the Kepler conjecture) involved long computer calculations. In contrast, Viazovska's proof for 8 and 24 dimensions is "stunningly simple". As well as for her work on sphere packing, Viazovska is also known for