SMS scnews item created by Anthony Henderson at Fri 4 Apr 2008 1518
Type: Seminar
Distribution: World
Expiry: 11 Apr 2008
Calendar1: 11 Apr 2008 1205-1255
CalLoc1: Carslaw 373
CalTitle1: Algebra Seminar: Yu -- The cyclotomic Birman-Murakami-Wenzl algebras
Auth: anthonyh@asti.maths.usyd.edu.au

Algebra Seminar

The cyclotomic Birman-Murakami-Wenzl algebras

Shona Yu

11th April, 12:05-12:55pm, Carslaw 373


Abstract

The motivation behind the definition of the Birman-Murakami-Wenzl (BMW) algebras may be traced back to an important problem in knot theory: namely, that of classifying knots (and links) up to isotopy, which leads to the study of link invariants. The algebraic definition of the BMW algebras uses generators and relations originally inspired by the Kauffman link invariant. They are intimately connected with the Artin braid group of type A, Iwahori-Hecke algebras of type A (the symmetric group), and with many diagram algebras (algebras with basis a given set of diagrams where multiplication is described by a simple diagram calculus). Geometrically, the BMW algebra is isomorphic to the Kauffman tangle algebra. The representations and the cellularity of the BMW algebra have now been extensively studied in the literature. These algebras also feature in the theory of quantum groups, statistical mechanics, and topological quantum field theory.

In view of these relationships between the BMW algebras and several objects of "type A", several authors have since naturally generalized the BMW algberas for other types of Artin groups.

Motivated by knot theory associated with the Artin braid group of type B, Häring-Oldenburg introduced the cyclotomic BMW algebras as a generalization of the BMW algebras associated with the Ariki-Koike algebras, aka the cyclotomic Hecke algebras of type G(k,1,n).

In this talk, we investigate the structure of these algebras and show they have a diagrammatic interpretation as a certain cylindrical analogue of the Kauffman tangle algebras. In particular, we provide a basis which may be explicitly described both algebraically and diagrammatically in terms of "cylindrical" tangles. This basis turns out to be cellular, in the sense of Graham and Lehrer.