Integrable Systems and Mathematical Physics

  • Quantum cohomology

    Forbenius manifolds

    The associativity condition of quantum cohomology provides links with integrable systems through the WDVV equations, Frobenius manifolds and noncommutative Schur polynomials.

  • Dynkin diagrams

    Dynkin diagram

    Dynkin diagrams encode the structure of Weyl groups and Lie algebras. Their representation theory is used in many areas, e.g. quantum many body systems and Frobenius manifolds.

  • Statistical models

    Vertex model

    The integrable six-vertex model is used to describe ferroelectrics such as ice as well as to count alternating sign matrices in combinatorics.

  • A deformation of a singularity

    Singularity

    The space of deformations of a singularity carries the structure of a Frobenius manifold.

  • Soliton theory

    Breather

    Solitons are special solutions to nonlinear partial differential equations but they also parametrize surfaces such as the one depicted above.

  • Ultradiscrete integrable systems

    Cellular automata

    Ultradiscrete integrable systems are cellular automata having soliton solutions. In the figure, three solitons with different speeds interact and each emerges unchanged apart from a phase shift.

Integrable systems is a branch of mathematics which has a long history but first came to prominance in the mid 1960's with the (mathematical) discovery of the soliton by Kruskal and Zabusky in connection with a dispersive shallow water wave problem. Since then this field has come to embrace many different aspects of mathematical physics. The group is working on a range of different problems in this area. Details of these are given below.

Dr Chris Athorne Senior lecturer

Geometric representation theory; algebraic curves;soliton theory

Member of other research groups: Geometry and Topology
Research student: Sophie Rachel Norman

Dr Mikhail Feigin Lecturer

Quantum integrable systems; Hadamard's problem; WDVV equations; random matrices

Member of other research groups: Geometry and Topology, Algebra

Dr Claire R Gilson Senior lecturer

Discrete and ultradiscrete integrable systems; quasideterminants

Dr Christian Korff Research Fellow of the Royal Society/Reader

Quantum integrable models; exactly solvable lattice models; low-dimensional QFT

Member of other research groups: Algebra
Research student: Mary Clark
Postgraduate opportunities: Integrable quantum field theory and Y-systems, Quantum spin-chains, exactly solvable lattice models and representation theory

Dr Jonathan J C Nimmo Reader

Discrete and ultradiscrete integrable systems; Darboux transformations; quasideterminants

Research student: Ying Shi

Prof Ian A B Strachan Professor of Mathematical Physics

Geometry and integrable systems; Frobenius manifolds; twistor theory and self-duality

Member of other research groups: Geometry and Topology
Research student: Richard Stedman

Dr Joachim Zacharias Reader

C*-algebras, their classification and amenability properties; special examples of C*-algebras; K-theory and non commutative topology, noncommutative dynamical systems, geometric group theory with applications to C*-algebras.

Member of other research groups: Geometry and Topology, Analysis, Algebra
Research students: Andrew Hawkins, Gabriel Tornetta

Mary Clark PhD Student

Research Topic: Quantum Integrable Systems
Supervisor: Christian Korff

Sophie Rachel Norman PhD Student

Research Topic: Geometry of higher genus Weierstrass P-functions
Supervisor: Chris Athorne

Ying Shi PhD Student

Research Topic: Inverse Scattering For Discrete Integrable Systems
Supervisor: Jonathan J C Nimmo

Richard Stedman PhD Student

Research Topic: Frobenius Manifolds
Supervisor: Ian A B Strachan

Quantum spin-chains, exactly solvable lattice models and representation theory (PhD)

Supervisors: Christian Korff
Relevant research groups: Algebra, Integrable Systems and Mathematical Physics

Quantum spin-chains and 2-dimensional statistical lattice models, such as the Heisenberg spin-chain and the six and eight vertex model remain an active area of research with many surprising connections to other areas of mathematics.

Some of the algebra underlying these models deals with quantum and Hecke algebras, the Temperley-Lieb algebra, the Virasoro algebra and Kac-Moody algebras. Recently these models have been applied in combinatorial representation theory to compute Gromov-Witten invariants and fusion coefficients in conformal field theory.

The sl(n)-WZNW fusion ring: a combinatorial construction and a realisation as quotient of quantum cohomology. with Catharina Stroppel. Adv Math 225, 1 (2010) 200-268; arXiv:0909.2347

 

Integrable quantum field theory and Y-systems (PhD)

Supervisors: Christian Korff
Relevant research groups: Integrable Systems and Mathematical Physics, Algebra

The mathematically rigorous and exact construction of a quantum field theory remains a tantalising challenge. In 1+1 dimensions exact results can be found by computing the scattering matrices of such theories using a set of functional relations. These theories exhibit beautiful mathematical structures related to Weyl groups and Coxeter geometry.

In the thermodynamic limit (volume and particle number tend to infinity while the density is kept fixed) the set of functional relations satisfied by the scattering matrices leads to so-called Y-systems which appear in cluster algebras introduced by Fomin and Zelevinsky and the proof of dilogarithm identities in number theory.