activity
20142026
most citedTwisted Steinberg algebras

12 citations · 35 across the 12 of their papers we have counts for

collaborators

13 papers

math.OA2026

Cartan inverse semigroups and twisted Steinberg algebras

Nathan Brownlowe, Lisa Orloff Clark, Ying-Fen Lin +1

We introduce the notion of a Cartan inverse semigroup and an (algebraic) semi-Cartan subalgebra in an -algebra A, providing a purely algebraic analogue of Cartan semigroups and…

math.OA2026

Lattices of strongly reflexive masa-bimodules

Rupert H. Levene, Ying-Fen Lin, Ivan G. Todorov

We characterise the density of the positive rank one subspace of a masa-bimodule in terms of its support. We prove that strongly reflexive masa-bimodules form a Boolean lattice und…

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.FA2023

Linear preservers on idempotents of Fourier algebras

Ying-Fen Lin, Shiho Oi

In this article, we give a representation of bounded complex linear operators which preserve idempotent elements on the Fourier algebra of a locally compact group. When such an ope…

math.RA2021★ 10 cited

Reconstruction of twisted Steinberg algebras

Becky Armstrong, Gilles G. de Castro, Lisa Orloff Clark +6

We show how to recover a discrete twist over an ample Hausdorff groupoid from a pair consisting of an algebra and what we call a quasi-Cartan subalgebra. We identify precisely whic…

math.RA2020★ 6 cited

Filtering germs: Groupoids associated to inverse semigroups

Becky Armstrong, Lisa Orloff Clark, Astrid an Huef +2

We investigate various groupoids associated to an arbitrary inverse semigroup with zero. We show that the groupoid of filters with respect to the natural partial order is isomorphi…

math.OA2020

The C*-algebra of the Boidol group

Ying-Fen Lin, Jean Ludwig

The Boidol group is the smallest non-*-regular exponential Lie group. It is of dimension 4 and its Lie algebra is an extension of the Heisenberg Lie algebra by the reals with the r…

math.RA2019★ 12 cited

Twisted Steinberg algebras

Becky Armstrong, Lisa Orloff Clark, Kristin Courtney +3

We introduce twisted Steinberg algebras over a commutative unital ring . These generalise Steinberg algebras and are a purely algebraic analogue of Renault's twisted groupoid C*…

math.FA2019

Schur null preserving maps

Ying-Fen Lin, Donal O'Cofaigh

We provide a characterisation of Schur multiplicative maps on both finite and infinite dimensional matrix spaces, and show that every surjective Schur multiplicative contraction is…

math.OA2018

Operator system structures and extensions of Schur multipliers

Ying-Fen Lin, Ivan G. Todorov

For a given C*-algebra , we establish the existence of maximal and minimal operator -system structures on an AOU -space. In the case $\mathca…

math.FA2016

A retract theorem for nilpotent Lie groups

Ying-Fen Lin, Jean Ludwig, Carine Molitor-Braun

Let $G= \exp(\g)$ be a connected, simply connected nilpotent Lie group. We show that for every -invariant smooth sub-manifold of , there exists an open relatively compa…

math.OA2015★ 3 cited

Positive extensions of Schur multipliers

Rupert H. Levene, Ying-Fen Lin, Ivan G. Todorov

We introduce partially defined Schur multipliers and obtain necessary and sufficient conditions for the existence of extensions to fully defined positive Schur multipliers, in term…

math.OA2014

The solvable Lie group : an example of an almost -C*-algebra

Junko Inoue, Ying-Fen Lin, Jean Ludwig

Motivated by the description of the C*-algebra of the affine automorphism group of the Siegel upper half-plane of degree 2 as an algebra of operator fields defined over…