See the calendar below for future seminars and events.
Following every Thursday seminar, attendees are welcome to come to one of our SMRI Afternoon Teas which take place on Thursday afternoons at 2pm on the Quadrangle Terrace, accessed through the entry in Quadrangle Lobby P and via the SMRI Common Room on level 4.
Upcoming and current events: seminars, workshops and course
Australian Geometric Topology Webinar, ‘From Lando graphs to extreme Khovanov homology for certain link families‘
Speaker: Seung Yeop Yang, Kyungpook National University
Date & time: Wednesday 15th April 2026 at 12 pm
Location: Zoom, with a screening in the SMRI Seminar Room (A12 Macleay Room 301)
Abstract: Khovanov homology is a categorification of the Jones polynomial and provides a powerful invariant of knots and links. One of the fundamental questions in the subject is the existence of geometric realizations of Khovanov homology. A notable answer was given by Lipshitz and Sarkar, who associated to each link a family of spectra whose reduced singular cohomology recovers its Khovanov homology. In a different direction, González-Meneses, Manchón, and Silvero identified the extreme Khovanov homology of a link diagram with the reduced (co)homology of the independence simplicial complex of the corresponding Lando graph.
In this talk, we present explicit realizations of the real-extreme Khovanov homology for certain families of links using Lando graphs. This establishes an explicit connection between combinatorial structures arising from link diagrams and topological realizations of their homological invariants. In particular, we describe such realizations for several families of links, including pretzel links and 2-bridge links. This is joint work with Mark H. Siggers, Jinseok Oh, and Hongdae Yun.
SMRI Seminar, ‘A physicist’s view on the assignment and optimal transport problems’
Speaker: Patrice Koehl, UC Davis
Date & time: Thursday 16th April 2026 at 1 pm
Location: SMRI Seminar Room (A12 Macleay Room 301)
Abstract: Optimal transport (OT) has become a discipline by itself that offers solutions to a wide range of theoretical problems in probability and mathematics. Despite its appealing theoretical properties, solving the OT problem involves the resolution of a linear program whose computational cost can quickly become prohibitive whenever the size of the problem exceeds a few hundred points. The recent introduction of entropy regularization, however, has led to the development of fast algorithms for solving an approximate OT problem. The successes of those algorithms have resulted in a popularization of the applications of OT in several applied fields including geometry, machine learning, and in data sciences in general. Problems remain, however, as to the numerical convergence of those regularized approximations towards the actual OT solution. In addition, the physical meaning of this regularization is unclear. In this talk, I will describe a novel approach to solving the discrete balanced and unbalanced OT problems using techniques adapted from statistical physics. I will illustrate applications of this framework to the problem of image comparison as well as to the problem of comparing three dimensional shapes.
Geometry & Topology Seminar, ‘Topology in quantum systems‘
Speaker: Adam Rennie, Wollongong University & University of Sydney
Date & time: Wednesday 22nd April 2026 at 12 pm
Location: SMRI Seminar Room (A12 Macleay Room 301)
Abstract: The machinery underpinning the Atiyah-Singer index theorem applies in much more general situations. I will give some examples from geometry and dynamics before describing two applications in quantum physics: topological insulators and scattering systems. I will not get into the technical weeds in this talk, focussing on how stable homotopy invariants arise. As an overview talk, this relies on many prior works and many coauthors. I will try to indicate these as I go along.
Seminar on Canonical Bases in Representation Theory
Dates and times: Wednesdays from 10 am –12 pm for the seminar, followed by a weekly exercise session from 1 pm –2 pm, starting from Wednesday 4th March, 2026
Location: SMRI Seminar Room (A12 Macleay Room 301)
Details: In this seminar, we aim to study the answers of the following motivating questions regarding irreducible representations of semisimple Lie algebras and related structures:
- How can we compute their characters?
- How can we compute tensor product decompositions?
- What are “canonical bases” for these modules?
A powerful tool introduced in the early 1990s, known as the canonical basis (Lusztig) or crystal basis (Kashiwara), provides a model to answer these questions.
We will start by learning about prototypical constructions that serve as motivation, before proceeding to the construction and properties of these modern bases: first studying Lusztig’s approach, and then Kashiwara’s approach.
This seminar will focus on the main ingredients and recipes used to motivate, construct and describe these bases: Kazhdan-Lusztig bases, Gelfand-Tsetlin bases, Lusztig’s algebraic construction, Lusztig’s geometric/topological construction, and Kashiwara’s crystal/global bases. More information on the Canonical Bases in Representation Theory website.