Seminário de Teoria de Cordas  

27/10/2008, 16:30 — 17:30 — Sala P3.10, Pavilhão de Matemática
Paulo Pires Pacheco, CAMGSD

(Exceptional) Generalised Geometry

We review recently introduced geometric tools used to characterize supersymmetric flux backgrounds, with special emphasis on Generalised Complex Geometry as developed by Hitchin. We then proceed to describe Exceptional Generalised Geometry, an extension of the latter formalism based on the exceptional Lie group $E_7(7)$ which achieves a full geometrization of all fluxes, including Ramond-Ramond fluxes. First we present the formal structure of the theory: the Exceptional Generalized Tangent bundle endowed with a non-trivial twisted topology and a corresponding gerbe structure, an  Exceptional Courant bracket and an Exceptional Generalized Metric in which the bosonic degrees of freedom of $11D$ supergravity (the traditional metric and the fluxes) enter on equal footing. We then show how this formalism may be used to rewrite part of $11D$ SUGRA in the language of $N=1$ $D=4$ supersymmetry and express the corresponding effective superpotential in a manifestly $E_7(7)$ form.