Preprint 2020-04
Johannes Broedel, André Kaderli, Oliver Schlotterer
Two dialects for KZB equations: generating one-loop open-string integrals.
Abstract: Two different constructions generating the low-energy expansion of genus-one configuration-space integrals appearing in one-loop open-string amplitudes have been put forward in refs. [1,2]. We are going to show that both approaches can be traced back to an elliptic system of Knizhnik–Zamolodchikov–Bernard(KZB) type on the twice-punctured torus.
We derive an explicit all-multiplicity representation of the elliptic KZB system for a vector of iterated integrals with an extra marked point and explore compatibility conditions for the two sets of algebra generators appearing in the two differential equations.
Preprint series: Institut für Mathematik, Humboldt-Universität zu Berlin (ISSN 0863-0976), 2020-04
91 pp.