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20172023
most citedTwisted Steinberg algebras

12 citations · 40 across the 9 of their papers we have counts for

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8 papers · 1 filter

math.OA2023★ 4 cited

The local bisection hypothesis for twisted groupoid C*-algebras

Becky Armstrong, Jonathan H. Brown, Lisa Orloff Clark +4

In this note, we present criteria that are equivalent to a locally compact Hausdorff groupoid being effective. One of these conditions is that satisfies the "C*-algebraic l…

math.OA2023★ 1 cited

Completely positive approximations and inductive systems

Kristin Courtney

We consider inductive systems of C*-algebras with completely positive contractive connecting maps. We define a condition, called C*-encoding, which is sufficient for the limit of t…

math.OA2023★ 1 cited

Nuclearity and CPC*-systems

Kristin Courtney, Wilhelm Winter

We write arbitrary separable nuclear C*-algebras as limits of inductive systems of finite-dimensional C*-algebras with completely positive connecting maps. The characteristic featu…

math.OA2022★ 6 cited

Alexandrov groupoids and the nuclear dimension of twisted groupoid -algebras

Kristin Courtney, Anna Duwenig, Magdalena C. Georgescu +2

We consider a twist over an étale groupoid . When is principal, we prove that the nuclear dimension of the reduced twisted groupoid -algebra is bounded by…

math.OA2020★ 2 cited

Universal -algebras with the Local Lifting Property

Kristin E. Courtney

The Local Lifting Property (LLP) is a localized version of projectivity for completely positive maps between -algebras. Outside of the nuclear case, very few $\mathrm…

math.OA2018

The universal C*-algebra of a contraction

Kristin Courtney, David Sherman

We say that a contractive Hilbert space operator is universal if there is a natural surjection from its generated C*-algebra to the C*-algebra generated by any other contraction. A…

math.OA2018★ 2 cited

Free products with amalgamation over central C*-subalgebras

Kristin Courtney, Tatiana Shulman

Let A and B be C*-algebras whose quotients are all RFD, and let C be a central C*-subalgebra in both A and B. We prove that the full amalgamated free product of A and B over C is t…

math.OA2017★ 2 cited

Elements of -algebras Attaining Their Norm in a Finite-Dimensional Representation

Kristin Courtney, Tatiana Shulman

We characterize the class of RFD -algebras as those containing a dense subset of elements that attain their norm under a finite-dimensional representation. We show further tha…