Dirk Kreimer (Humboldt-Universität zu Berlin)
Title: Algebra and Monodromy in Amplitudes
Abstract: We investigate the structure of Green functions and amplitudes in QFT. Such functions appear as solutions to Dyson–Schwinger equations which are fixed point equations driven by a particular Hochschild cohomology. Eventually this gives rise to an expansion in multivalued function often related to (elliptic or generalized) polylogarithms. Their monodromies relate to algebraic and combinatoric properties of graphs. We will discuss this relation in some detail.