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Seminar by Richard Hepworth (Copenhagen University)

Title: Field Theories from Lie Groups

2013.11.01 | Christine Dilling

Date Wed 11 May
Time 16:15 17:15
Location Aud. D3


A homological field theory (or HFT) is an algebraic structure governed by surfaces and their mapping class groups. Although the name is inspired by theoretical physics, HFTs really belong to topology: an HFT is simply a functor on an appropriate category of cobordisms.

After reviewing these definitions I will explain how to obtain a HFT from a compact Lie group G. This recovers some classic algebraic structures on the homology of G and BG, and much new data besides. If time permits then I will explain the connection with Chern-Simons theory and the "parameterised umkehr maps" used to build the HFT.

This is joint work with Anssi Lahtinen.