Jacob Tsimerman (born 1988) is a Canadian mathematician at the University of Toronto specialising in number theory and related areas.
In 2003 and 2004 he represented Canada in the International Mathematical Olympiad (IMO) and won gold medals both years, with a perfect score in 2004.
He was awarded for "outstanding work in analytic number theory and arithmetic geometry, including breakthroughs on the André-Oort and Griffiths conjectures".
[9] Together with Jonathan Pila, Tsimerman demonstrated the André–Oort conjecture for Siegel modular varieties.
Later, he completed the proof of the full André-Oort conjecture for all moduli spaces of abelian varieties by reducing the problem to the averaged Colmez conjecture which was proved by Xinyi Yuan and Shou-Wu Zhang as well as independently by Andreatta, Goren, Howard and Madapusi-Pera.