(1) Presentation(s)
Lun. 17/11/2014 14:00 Petite Ourse, Bâtiment 13, Etage 1 ANDRIOT David (AEI, Potsdam, Allemagne) Candidat CNRS section 2 NS-branes and non-geometric fluxes in ten dimensions (Physique Théorique) The non-geometric fluxes are specific gaugings that appear in four-dimensional (4D) gauged supergravities. They generate particular terms in the potential, that are of phenomenological interest (moduli stabilisation, de Sitter vacua). However, obtaining them from a compactification of a standard ten-dimensional (10D) supergravity is a priori not possible, as they are thought to descend from 10D backgrounds exhibiting a so-called non-geometry. After reviewing these ideas, I will present a reformulation of the standard (NSNS sector of) 10D supergravity into a new 10D theory named beta-supergravity. The latter contains 10D non-geometric fluxes, and can reformulate a non-geometric background into a geometric one. This theory thus provides an uplift to the aforementioned 4D supergravities. In addition, this framework allows to write 10D Bianchi identities for non-geometric fluxes. Those get corrected by a source term and boil down to Poisson equations in presence of NS-branes, as for an NS5-brane or a KK-monopole; in particular the non-geometric Q-flux is sourced by the new exotic 5_2^2- or Q-brane. I will finally comment on supersymmetry for this theory. Pour plus d'informations, merci de contacter Alexandrov S. |