Recent seminars

Europe/Lisbon
Online

Matteo Mucciconi, National University of Singapore

Skew RSK dynamics

The skew RSK dynamics is a discrete 2 dimensional deterministic dynamics introduced by Imamura, Sasamoto and myself. It is an integrable system in the sense that it possesses infinitely many conservation laws and a rich set of symmetries. The analysis of its scattering relations produces a nontrivial correspondence which generalizes the celebrated Robinson-Schensted-Knuth bijection. Such correspondence provides a bijective proof of summation identities between special symmetric polynomials, which describe the law of certain interacting particle systems or directed polymer models and allow their asymptotic analysis.

Europe/Lisbon
Room P3.10, Mathematics Building — Online

Peter Jossen
Peter Jossen, King's College London

On E-functions, exponential integrals, and their differential equations

E-functions are power series which solve a linear differential equation, and whose coefficients are algebraic numbers subject to a growth condition of arithmetic nature. The exponential series is an example of an E-function, as well as Bessel functions with integer parameter. Siegel introduced these functions in 1929 with the goal of generalising the Hermite-Lindemann-Weierstrass theorem on the transcendence of the values of the exponential function at algebraic numbers.

In a joint work with Javier Fresán, we found that certain exponential integrals associated with algebraic varieties give rise to differential equations whose solutions can be expressed in terms of E-functions. I will present some of this work, and talk about the inverse problem of representing a given E-function, or rather the associated differential equation, by an exponential integral, and relating these objects thereby to algebraic geometry.