Kavli IPMU Komaba Seminar

Seminar information archive ~07/23Next seminarFuture seminars 07/24~

Date, time & place Monday 16:30 - 18:00 002Room #002 (Graduate School of Math. Sci. Bldg.)


17:00-18:30   Room #128 (Graduate School of Math. Sci. Bldg.)
Hans Jockers (The University of Bonn)
Characteristic classes from 2d renormalized sigma-models (ENGLISH)
[ Abstract ]
The Hirzebruch-Riemann-Roch formula relates the holomorphic Euler characteristic
of holomorphic vector bundles to topological invariants of compact complex manifold.
I will explain a generalization of the Mukai's modified first Chern character map, which
introduces certain characteristic classes that have not been considered in this form by
Hirzebruch. This naturally leads to the characteristic Gamma class based on the Gamma
function. The characteristic Gamma class has a surprising relation to the quantum theory
of certain 2d sigma-models with compact complex manifolds as their target spaces. I will
argue that the Gamma class describes perturbative quantum corrections to the classical
theory of those sigma models.