Toms-winter conjecture and tracial state space with non-compact extreme boundary

Wei Zhang, Purdue University

Abstract

Let A be a unital simple separable C*-algebra. If A is nuclear and infinite-dimensional, it is known that strict comparison of positive elements is equivalent to Z-stability if the extreme boundary of its tracial state space is compact and of finite covering dimension. In this thesis we provide the first proof of this result in the case of certain non-compact extreme boundaries. Additionally, if A has strict comparison of positive elements, it is known that the Cuntz semigroup of this C *-algebra is recovered functorially from the Murray-von Neumann semigroup and the tracial state state space whenever the extreme boundary of the tracial state space is compact and of finite covering dimension. We extend this result to the case of a countable extreme boundary with finitely many cluster points.

Degree

Ph.D.

Advisors

Toms, Purdue University.

Subject Area

Mathematics

COinS