Unless otherwise stated, seminars
will take place in Seminar Room of the
ICMS
at
the University of Edinburgh.

Please contact the organisers Tim
Adamo (UoE) or Bart Vlaar
(HW)
with any questions regarding the seminars.

Owing to the ongoing COVID-19 situation, until further notice the EMPG seminars are held online using Zoom every Wednesday 16:00-17:00 unless otherwise stated below.
Instructions for Zoom will be shared prior to each seminar.
Wednesday,
27 May 2020

16:00

Eduardo Casali
(UC Davis)

Recent work has reinterpreted and unified relations among tree-level string theory amplitudes known since the 80's in the language of twisted homology in the moduli space of punctured Riemann surfaces. This new geometric understanding allows not only for more efficient computations of explicit forms for these relations but also opens the way towards their generalization beyond tree-level, that is beyond genus 0. In this talk I'll review this interpretation of tree-level string amplitudes, in particular the monodromy relations as twisted homology relations and the Kawai-Lewellen-Tye (KLT) as twisted intersection numbers, and report on recent work by S. Mizera, P. Tourkine and I on generalizing these concepts to higher genus. I will also discuss their field theory limit and their relevance to field theory amplitude relations, with particular interest in the color-kinematics duality and the double-copy procedure.

Wednesday,
3 June 2020

13:00

Martin Hallnäs
(Chalmers University, Göteborg)

Lassalle and Nekrasov discovered in the 1990s a surprising correspondence between the rational Calogero–Moser N-body system with a harmonic term and its trigonometric version. In the quantum case, the correspondence amounts to a specific operator on the algebra of symmetric functions in N variables that intertwines between the quantum integrals of these two systems.
For special coupling parameter values, I will explain how to extend the Lassalle-Nekrasov correspondence from the symmetric to the much wider quasi-invariant setting and, time permitting, present a conceptual explanation of the correspondence using the rational Cherednik algebra.
The talk is based on joint work with Misha Feigin and Alexander Veselov.