In the middle of 1980's, motivated by study of singularity theories, K. Saito introduced the notion of "elliptic root systems". Roughly speaking, they are root systems with two null directions. Furthermore, he

The polaron describes a charged particle moving in a polarizable medium. Due to the interaction with the medium, the particle appears to be heavier that it would be outside the medium. This

La résolution des EDO avec des singularités irrégulières en domaine complexe peut être faite soit formellement, soit analytiquement. Au niveau formel, une méthode de Poincaré permet de construire un frame de solutions

The coalgebra symmetry method, developed by is one of the most fruitful techniques to produce systematically an N-dimensional Hamiltonian integrable system from a 1-dimensional system. This method has been recently adapted for

How are bulk strings related to boundary Feynman diagrams? I will give an overview of my work with Rajesh Gopakumar on deriving the closed string dual to the simplest possible gauge theory,

I will talk about models of two dimensional random growth (namely, polynuclear growth) which can be translated into probability laws on integer partitions by way of the RSK algorithm. As a consequence,

The local information of a 2d rational conformal field theory (RCFT) is encoded in a vertex operator algebra, whose modules constitute a modular fusion category C. The collection of global observables of

Recently, the study of higher categories of topological defects in quantum field theory has gained significant attention due to their connection to categorical symmetries. These higher categories exhibit noteworthy additional structures, depending

Cosmic strings (or vortex strings) are topological defects arising when U(1) symmetry is spontaneously broken in quantum field theories. In three-dimensional relativistic systems, loops of cosmic strings are known to be unstable

Four-dimensional Wess-Zumino-Witten (4dWZW) models are analogous to the two dimensional WZW models and possesses aspects of conformal field theory and twistor theory .  Equation of motion of the 4dWZW model is the

A fundamental prediction of quantum physics is the existence of random fluctuations everywhere in vacuum. This is one of the most remarkable and central ideas in quantum field theory which manifests itself