Our Team

Geordie Williamson, Director

Professor Geordie Williamson received his undergraduate degree from the University of Sydney and completed his PhD at the University of Freiburg in 2008. He held subsequent positions at the University of Oxford and St. Peter’s College, and worked at the Max Planck Institute for Mathematics in Bonn for five years as an Advanced Researcher. Geordie returned to the University of Sydney as a Professor in 2017 and established the Sydney Mathematical Research Institute with Professor Anthony Henderson.

Geordie’s interests lie in basic questions in representation theory that need extremely sophisticated techniques from algebraic geometry, Hodge theory, or higher category theory to resolve.

Awards and honours

• Prize for Excellence in Mathematics, NSW Premier’s Prizes for Science & Engineering (2022)
• Distinguished Visiting Professor, Institute for Advanced Study (2020)
• Christopher Heyde Medal of the Australian Academy of Science, for research in the mathematical sciences (2019)
• Medal of the Australian Mathematical Society (2018)
• Fellow of the Australian Academy of Sciences, Fellow of the Royal Society (elected to both in 2018)
• Clay research Award, European Mathematics Society Prize, 2017 New Horizons Prize (with Ben Elias), Chevalley Prize of the American Mathematics Society (all awarded 2016)
• View interviews and other media featuring Geordie on the SMRI in The News page

Stephan Tillmann, Executive Director

Professor Stephan Tillmann studied mathematics and philosophy in Mainz (Germany) and Melbourne (Australia). After graduating with a doctoral thesis in low-dimensional topology from the University of Melbourne, he spent three years each in Montreal, Melbourne and Brisbane. Stephan joined the University of Sydney in 2011 and currently holds the position of Professor of Geometric Topology.

Stephan’s specialist expertise is rooted in the topology and geometry of low-dimensional manifolds, and his research interests extend to neighbouring areas in mathematics and theoretical computer science.

Awards and honours

• Friedrich Wilhelm Bessel Research Award, Alexander von Humboldt Foundation (2021)
• Australian Research Council Future Fellowship (2018-2021)
• Faculty of Science Learning and Teaching Award, The University of Sydney (2015)
• B.H. Neumann Prize, Australian Mathematical Society (2001)

Dr Renjie Feng, Postdoctoral Research Fellow

Renjie Feng completed his PhD at Northwestern University. He joined the Sydney Mathematical Research Institute in late 2023.

Renjie is interested in probability, especially in random matrices and random geometry.

Dr Harini Desiraju, Postdoctoral Research Associate

Harini Desiraju is a postdoctoral researcher at SMRI and the University of Sydney. She enjoys thinking about several questions in mathematical physics and her research mostly focuses on integrable systems and conformal field theories.

Harini graduated with a PhD in Geometry and Mathematical Physics from SISSA, Trieste in 2021 under the supervision of Marco Bertola and Tamara Grava. She has since been a postdoc at University of Birmingham and SLMath (formerly MSRI). 

Dr Thomas Le Fils, Postdoctoral Research Associate

Thomas Le Fils completed his PhD at Sorbonne Université. He joined the Sydney Mathematical Research Institute as a postdoctoral researcher in late 2022. Thomas is interested in the study of geometric structures on surfaces and their links with character varieties.

Dr Ashvni Narayanan, Postdoctoral Researcher

Ashvni Narayanan is a postdoctoral researcher at SMRI and the University of Sydney. Her interests include (but are not restricted to) number theory, formal verification, machine learning and discrete mathematics..

Her PhD, completed at Imperial College London, comprised of formalization of p-adic L-functions in an automated theorem prover called Lean 4. Ashvni also interested in machine learning and have been experimenting with translation of natural language to Lean code using Large Language Models.. 

Dr Alan Stapledon, Research Affiliate

Alan Stapledon graduated from the University of Sydney in 2003, with the highest average grade of any undergraduate science student in that year. He completed a PhD in mathematics at the University of Michigan in 2009, winning the award for best PhD thesis. He worked as a postdoctoral researcher at MSRI at Berkeley, University of British Columbia and University of Sydney, over a 3 year period. He retired from Renaissance Technologies LLC, after working as an equities researcher for 9 years and joined SMRI as a research affiliate in September 2021.

Alan is interested in connections between algebraic geometry and combinatorics. More specifically, he is studying intersections between Hodge theory, toric geometry and Ehrhart theory.

Kate Doyle, Executive Officer

Kate moved to Australia from the UK in 2001 and has worked at The University of Sydney since January 2005, primarily in the Business School. She has had success as a large-team manager, an engaged collaborator, a proactive trouble-shooter and an energetic contributor to initiatives and projects. She endorses a positive workplace culture and is currently Wellbeing Champion for the School of Mathematics and Statistics.

Kate Doyle commenced with SMRI in December 2021 and has overall responsibility for the operational management and administrative support of the Institute. Kate also oversees the work activities and growth of the professional staff team and collaborates closely with them on delivering best possible work outcomes.

Dr Larissa Fedunik-Hofman, Communications Coordinator

Larissa Fedunik-Hofman studied Mechanical Engineering and Arts at the University of Queensland and the Technical University of Munich. While undertaking a PhD in solar chemistry at the University of Newcastle, she began working in STEM publishing and science communications. After graduating, she worked at the Australian Academy of Science producing educational articles and videos.

Larissa joined SMRI in December 2020. Larissa blogs about science and history and has written articles for New Scientist, Smithsonian Magazine and RenewEconomy.

Hannah Bryant, Administration Officer

Hannah Bryant joined SMRI in June 2019 and has over 15 years of experience in office administration in the private sector. She has a Masters of Research, majoring in Egyptology, from Macquarie University.

Anthony Henderson, Founding Executive Director

Anthony Henderson received his undergraduate degree from the University of Sydney and obtained his PhD from the Massachusetts Institute of Technology in 2001. He worked at the University of Sydney from July 2001 to June 2022, becoming a Professor of Mathematics in 2016. He is also a founding Director of the Simon Marais Mathematics Competition for undergraduates in the Asia-Pacific region. In April 2022 he was farewelled from SMRI at the Hendoff.

Broadly speaking, he is interested in geometric and combinatorial aspects of representation theory. In particular, he studies the geometry of nilpotent varieties and Springer fibres, and their generalisations.

Awards and honours

• Medal of the Australian Mathematical Society (2012)
• Christopher Heyde Medal of the Australian Academy of Science, for research in the mathematical sciences (2011)
• Faculty of Science Citation for excellence in teaching (2009)

Dr Bregje Pauwels

Bregje Pauwels is a lecturer at Macquarie University and a member of the algebra research group. Prior to this, she was a postdoctoral researcher at the University of Sydney under the supervision of Kevin Coulembier and Oded Yacobi, and a postdoctoral fellow at the Australian National University under the supervision of Amnon Neeman.

Bregje completed her PhD in 2016 at the University of California, Los Angeles, where her research mentor was Paul Balmer. She studies triangulated categories and tensor categories in representation theory and algebraic geometry.

Kate Ridler

Kate Ridler was SMRI’s Executive Officer from January 2019 to October 2021. She was responsible for the effective implementation of the Institute’s operational and administrative processes, as well as having oversight over the growth and management of the professional staff.

Kate moved to Australia from the UK 15 years ago and spent 13 of those years working in various Senior Administrative roles at the University of Sydney. Kate recently returned to the UK with her son to begin the next chapter in their lives. Kate is an advocate for child welfare and stopping domestic family violence and is studying to obtain a certificate in Domestic and Family Violence support.