Magnetic amplitudes for strings in a background 3-form H involve a 2-form potential B integrated on surfaces of arbitrary topology. We propose a random matrix model whose topological expansion lead to a discretized version of these amplitudes, in the case of a propagation on a finite space X quotiented by a finite group G. Besides the fluxes induced by B, they also involve topological defects on the surface, weighted by additional fields that are constructed using the group cohomology of G.
By Maïté Dupuis
By Johannes Thürigen
By Antônio Duarte Pereira
By Sumati Surya
By Riccardo Martini
By Raimar Wulkenhaar
By Valentin Bonzom
By Gaëtan Borot
By Timothy Budd
By Jan Ambjorn
By Laurent Baulieu
By François David
By Reiko Toriumi
By Thomas Krajewski
By Simone Speziale
By Marc Levine
By Claudio Dappiaggi
By Ronnie Pavlov
By Tamara Kucherenko
