Francesco Fournier-Facio (University of Cambridge)

Title:
Bounded cohomology and displacement.

Abstract:
Bounded cohomology is a functional-analytic analogue of group cohomology that is central to rigidity theory, dynamics, geometric topology, and geometric group theory. A major drawback is the failure of excision, which renders even basic computations currently out of reach.

One of the few cases where non-trivial computations are possible is transformation groups with certain displacement properties that are classically used in homology and stable commutator length. I will introduce a new algebraic criterion that captures this, is satisfied in many interesting settings, and implies vanishing in all degrees and with a large class of coefficients.

Joint with Caterina Campagnolo, Yash Lodha, and Marco Moraschini

Schedule:
09:30-11:00 RTG lecture 1 (Alexander Thomas), SR. 2.058
11:00-11:30 Get-Together with Speaker, SR. 2.058
11:45-12:45 Colloquium: Francesco Fournier-Facio, SR. 1.067
13:15 Lunch at Max Rubner Institute | Daily Menu
14:30 Coffee in math building, SR. 1.058
14:45-15:15 Informal meeting of PhD students, Room 1.062
15:15-16:45 RTG lecture 2 (Alexander Thomas), SR. 1.067

KA