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Ralph Blumenhagen, Max-Planck-Institut für Physik, München

Non-associative Deformations of Geometry in Double Field Theory

Non-geometric string backgrounds were proposed to be related to a non-associative deformation of the space-time geometry. In this talk, using the flux formulation of double field theory (DFT), the structure of non-associative deformations is analyzed in detail. It is argued that on-shell there should not be any violation of associativity in the effective DFT action. I discuss two possible non-associative deformations of DFT featuring two different ways how on-shell associativity can still be kept.