报告题目:Dimension, comparison, and almost finiteness

报告人:David Kerr , Professor , Texas A&M University

报告时间:2017年6月15日下午16:30

报告地点:数学楼306

报告摘要:I will explain how one can develop a dynamical version of some of the theory surrounding the Toms-Winter conjecture for simple separable nuclear C*-algebras. In particular, I will introduce a notion of almost finiteness for group actions on compact spaces as an analogue of both hyperfiniteness in the measure-preserving setting and of $/mathcal{Z}$-stability in the C*-algebra setting. This generalizes Matui's concept of the same name from the zero-dimensional context and is related to dynamical comparison in the same way that $/mathcal{Z}$-stability is related to strict comparison in the Toms-Winter context. For free minimal actions of countably infinite groups on compact metrizable spaces the property of almost
finiteness implies that the crossed product is $/mathcal{Z}$-stable, which leads
to new examples of classifiable crossed products.