activity
20242026
collaborators

8 papers

math.OA2026

Cartan subalgebras in self-similar graph -algebras

Dawn Archey, Anna Duwenig, Shanshan Hua +3

For a self-similar graph , we find a distinguished subgroupoid of the associated path groupoid -- the symmetric cycline subgroupoid $\mathcal{S}_{\text{…

math.OA2025

Non-traditional C*-diagonals in twisted groupoid C*-algebras

Anna Duwenig

We identify which conditions on an open normal subgroupoid of a LCH étale groupoid with twist are necessary and sufficient for the subgroupoid's reduced twisted C*-algebra to be a…

math.OA2025

The Operator Algebras Mentor Network: Impact of Community-Based Mentoring

Anna Duwenig, Kari Eifler, Priyanga Ganesan +4

This paper aims to determine if membership within the Operator Algebras Mentor Network (OAMN) is beneficial to its members. The OAMN is an international mentoring initiative that o…

math.OA2025

Non-traditional Cartan subalgebras in twisted groupoid C*-algebras

Anna Duwenig, Dana P. Williams, Joel Zimmerman

Well-known work of Renault shows that if is a twist over a second countable, effective, étale groupoid , then there is a naturally associated Cartan subalgebra of…

math.OA2024

Norm upper-semicontinuity of functions supported on open abelian isotropy in étale groupoids (a corrigendum to "Reconstruction of groupoids and C*-rigidity of dynamical systems," Adv. Math 390 (2021), 107923)

Toke Meier Carlsen, Anna Duwenig, Efren Ruiz +1

We consider étale Hausdorff groupoids in which the interior of the isotropy is abelian. We prove that the norms of the images under regular representations, of elements of the red…

math.OA2024

The Zappa-Szép product of twisted groupoids

Anna Duwenig, Boyu Li

We define and study the external and the internal Zappa-Szép product of twists over groupoids. We determine when a pair of twists over a matched pair $(\mathcal{…