HET seminar: Stephan Stieberger

Speaker: Stephan Stieberger

Title: Monodromy Relations in Higher-Loop String Amplitudes

Abstract: New monodromy relations of loop amplitudes are derived in open string theory. We particularly study N-point one-loop amplitudes described by a world-sheet cylinder (planar and non-planar) and derive a set of relations between subamplitudes of different color orderings. Their field-theory limits and alpha’-expansions are discussed. The latter involve elliptic iterated integrals with the resulting periods giving rise to multiple elliptic zeta values. Furthermore, our monodromy relations involve new objects for which we present an interpretation in terms of open string scattering amplitudes in the presence of a non-trivial gauge field flux.