Online seminar, this Tuesday at 10:00, U. Haifa Topology & Geometry seminar on June 9, 2020
Geometry & Topology Seminar
Speaker: Xing Gu, Max Planck Institute for Mathematics
Topic: The topological period-index problem
Place: This is an online seminar. Please email me “ozgurbayindir at gmail dot com” for the Zoom ID and password.
Time: 10:00
Date: Tuesday, June 9, 2020
Abstract:
The topological period-index problem (TPIP), an analogue to the long-standing period-index conjecture in algebraic geometry, concerns a given torsion class α in the 3rd integral cohomology group of a topological space X and various principal PU_n-bundles over X associated to α. Here PU_n is the projective unitary group of order n, i.e., the unitary group U_n modulo invertible scalars. TPIP was first considered by Antieau and Williams in an attempt to find a counterexample to the period-index conjecture, but later turned out to have its own significance.
In this talk I will introduce recent work, joint with Crowley and Haesemeyer on the topological period-index problems over finite CW-complexes and closed manifolds.