Date

May 11, Monday, 10:30--11:30, 2026

Place

Room 206, RIMS

Speaker

Naoki Genra (Toyama University)

Title

BRST cohomology for linear quiver gauge theory and associated Poisson vertex algebras

Abstract

　 BRST cohomology is an analogous method with Hamiltonian reductions to obtain new vertex algebras from given ones. Using the construction of physicists, we give the BRST cohomology vertex algebras of 3d N=4 quiver gauge theory, and compute the associated graded Poisson vertex algebras. Then we show how to relate these Poisson vertex algebras to Higgs branches of linear quiver gauge theory.

Date

April 27, Monday, 10:30--11:30, 2026

Place

Room 206, RIMS

Speaker

Leonid Ryvkin (Claude Bernard University Lyon 1)

Title

Tepui fibrations and singular vector bundles

Abstract

　 As a differential-geometric object, a tepui fibration is a type of singular fiber bundle with smooth base space and smooth fibers, however the fiber dimension might jump when moving from one base point to another. Tepui fibrations naturally turn up in differential geometry, when one is quotienting by a smooth family of symmetries, which degenerates at certain points, e.g. in the context of singular foliations. In this talk I will give an introduction to tepui fibrations and show how they provide a natural way to extend the classical Serre-Swan theorem beyond the setting of projective modules.
Based on joint work with Alfonso Garmendia and David Miyamoto, https://arxiv.org/pdf/2510.20936.