# Astrid an Huef

**Professor** School of Mathematics and Statistics

#### Qualifications

PhD in Mathematics, 1999, Dartmouth College

#### Research Interests

Analysis is the branch of mathematics that is concerned with limiting processes, and functional analysis is the subbranch that deals with infinite-dimensional phenomena. Functional analysis received a major impetus from the advent of quantum mechanics, where the models involve linear operators on infinite-dimensional spaces. Operator algebra was developed as a framework for studying systems of linear operators, and is an important tool in many areas of modern mathematics.

Astrid is a functional analysts who specialises in operator algebras that impinge on other areas of modern mathematics such as dynamics, graph theory, number theory and harmonic analysis. She studies operator algebras associated to dynamical systems, combinatorial structures such as directed graphs, and groups and groupoids. The broad idea is to see properties of the operator algebra reflected in the underlying structure. Recently, Astrid has become interested in purely algebraic versions of the operator algebras of graphs and groupoids.

Astrid's research group includes; Prof Iain Raeburn, AProf Lisa Clark, and postdoc Dr James Fletcher who is supported by their joint Marsden grant. The group has strong international links, and an active program of collaboration spanning four continents.

#### Publications

See Astrid's papers on the preprint server arXiv.org. You can see her published papers on MathScinet (subscription required).

#### Supervision interest

Astrid is happy to be approached by potential students (Honours, Masters, PhD). For Honours projects, the required background to work with her is either some 3rd-year algebra or some 3rd-year analysis.

#### Past PHD students

Ilija Tolich (PhD 2017, University of Otago), Algebras of Partial Isometries

Daniel van Wyk (PhD 2017, University of Otago), The Structure of GCR and CCR Groupoid C* Algebras

Zahra Afsar (PhD 2016, University of Otago), Equilibrium States on Toeplitz Algebras

Richard MacNamara (PhD, 2016, University of Otago) KMS States of Graph Algebras with a Generalised Gauge Dynamics

Robert Hazlewood (PhD 2013, University of New South Wales), Categorising the Operator Algebra of Groupoids and Higher-Rank Graphs

Ariyani (PhD 2008, University of New South Wales), The Generalized Continuous Wavelet Transform on Hilbert Modules