# Algebra and Topology Seminar

These seminars invite speakers from a broad spectrum of areas, including algebraic and differential geometry, algebraic topology, low-dimensional topology, representation theory, quantum algebra, and number theory.

There is also a Google calendar for the seminar, which typically lists scheduled speakers in advance of their posting here.

## Upcoming events

31

Jul

2018

3.30–4.30pm 31 July 2018

Dr Jack Hall, The University of Arizona

Algebra and topology seminar

## Past events

12

Jun

2018

### Hyperplane arrangements associated to symplectic quotient singularities »

Algebra and topology seminar

22

May

2018

### The GNVW index and its generalizations. »

Algebra and topology seminar

15

May

2018

### Waldhausen theorem pre-talk »

Algebra & topology seminar

08

May

2018

### The strong monodromy conjecture for Weyl hyperplane arrangements »

The Bernstein-Sato polynomial is a subtle invariant of a hypersurface singularity that is closely related to the log-canonical threshold.

01

May

2018

### On the critical loci of finite maps »

Consider a rational function f(z) of degree n. To f(z), we can associate its set of critical points, namely the points z where the derivative vanishes.

24

Apr

2018

### An approach to the local geometric Langlands conjectures via higher representation theory »

The local geometric Langlands conjectures, formulated by Frenkel and Gaitsgory, give a geometric description of the representation categories of affine Lie algebras at the critical level.

20

Apr

2018

### Gauging modular categories »

Gauging is a procedure for taking a modular category equipped with an action by a finite group, and producing a new modular category.

03

Apr

2018

### From ADE to Fermat curves and beyond: modular invariants for the quantum groups »

In 1987, Cappelli-Itzykson-Zuber classified the conformal field theories (more precisely their modular invariant partition functions) associated to the sl(2) quantum groups.

20

Mar

2018

### Quantum G2 at roots of unity: diagrams vs. algebra »

For generic $q$, Kuperberg's $G_2$ spider agrees with the category of representations of the quantum group. What happens when $q$ is a root of unity?

13

Mar

2018

### Dual and classical generators of Artin groups of spherical type »

The aim of the talk is to explain how to express the generators of the braid group coming from the dual braid monoid (and more generally the simples, that is, the divisors of the Garside element of the dual monoid) in terms of the classical generators.

27

Feb

2018

### Localising modules, rings, and spectra. »

Given a ring R and a multiplicative subset S of R, then one can localise R at S using a number of different constructions.

20

Feb

2018

### Modular representation theory via categorification and knot theory »

We will study the category of modular representations of the special linear Lie algebra in positive characteristic; we focus on the case with a central Frobenius character given by a nilpotent whose Jordan type is a two-row partition.

13

Feb

2018

### Grothendieck duality made simple »

Until very recently the accepted wisdom was that there is no clean way to set up the foundations of Grothendieck duality. This changed drastically recently: we have discovered a clean way to prove everything.

06

Feb

2018

### Functoriality of link homologies and higher representation theory »

In the talk I will discuss how to obtain functoriality for coloured Khovanov–Rozansky homology.

28

Nov

2017

### Combinatorics of level 0 representations »

Recent work of Kato and Kato-Naito-Sagaki has provided an improved understanding of the combinatorics of integrable level 0 representations of the affine Lie algebra.