Some de Sitter solutions of four-dimensional gauged supergravity have been found with non-geometric fluxes turned on. Uplifting those to ten-dimensional supergravity and string theory is challenging, as they should naively come from so-called non-geometries. After reviewing these concepts and giving examples, I will introduce a reformulation of standard supergravity into a new ten-dimensional theory that contains directly non-geometric fluxes. This "beta-supergravity" then allows the uplift in some cases; in other words, a standard dimensional reduction of this theory leads to some of the four-dimensional gauged supergravities of interest. This theory also provides a good description of the Q-brane, a new exotic brane T-dual to the NS5-brane. Finally, I will say a word on the interesting Generalized Geometry formulation of beta-supergravity.
The seminar is free and open to all. Seating is on a first-come, first-served basis.
