Uploaded June 2026 | Updated September 2026, 3 days ago
The 25th Midrasha Mathematicae on Groups, Expanders and Codes -- Celebrating Alex Lubotzky's 70th birthday.
Day 3, Session 4
Speaker: Francesco Fournier-Facio (Cambridge)
Title: On quasimorphisms
Abstract: A quasimorphism on a group G is a function from G to the reals that satisfies the homomorphism relation up to a bounded error. I will give an introduction to these objects, discuss the important role they play in many areas of mathematics, and report on recent developments on constructions and obstructions. I will then focus on the generalisation to non-commutative targets, and report on joint work with Sami Douba, Sam Hughes and Simon Machado.
The 25th Midrasha Mathematicae on Groups, Expanders and Codes -- Celebrating Alex Lubotzky's 70th birthday.
Day 3, Session 4
Speaker: Francesco Fournier-Facio (Cambridge)
Title: On quasimorphisms
Abstract: A quasimorphism on a group G is a function from G to the reals that satisfies the homomorphism relation up to a bounded error. I will give an introduction to these objects, discuss the important role they play in many areas of mathematics, and report on recent developments on constructions and obstructions. I will then focus on the generalisation to non-commutative targets, and report on joint work with Sami Douba, Sam Hughes and Simon Machado.
