Cohomological obstructions to lifting properties for full C*-algebras of property (T) groups

Abstract: We will introduce and discuss the lifting property (LP) and local lifting property (LLP) for full group C*-algebras. We will then introduce a new method to refute these properties, based on non-vanishing of second cohomology groups. This will allow us to derive that many natural examples of (relative) property (T) groups fail the LLP, and further large classes fail the LP. This is based on joint work with Adrian Ioana and Matthew Wiersma.

geometric topologynumber theoryoperator algebrasrepresentation theory

Audience: researchers in the topic

( slides | video )

Noncommutative Geometry in NYC

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