G-kernels and crossed modules

Add to your list(s) Download to your calendar using vCal

• Sergio Giron pacheco (KU Leuven)
• Friday 04 July 2025, 10:10-10:30
• External.

If you have a question about this talk, please contact nobody.

TGAW01 - Crossed products and groupoid C*-algebras

For a discrete group G and a C-algebra A a G-kernel on A is a homomorphism from G to outer automorphism group of A. To any G-kernel, one can associate a cohomological obstruction to lifting it to a group action on A. In a recent work with Evington and subsequent work of Izumi, new cohomological invariants of G-kernels were introduced. These invariants place restrictions to the possible values of lifting obstructions on C-algebras. In this talk, I will discuss how these obstructions can be interpreted as cohomology with coefficients in crossed modules and the benefits of this framework. This is joint work with Masaki Izumi and Ulrich Pennig.

This talk is part of the Isaac Newton Institute Seminar Series series.

This talk is included in these lists:

• All CMS events
• External
• Featured lists
• INI info aggregator
• Isaac Newton Institute Seminar Series
• School of Physical Sciences
• bld31

Note that ex-directory lists are not shown.