S-duality in Twistor Space Auteur(s): Alexandrov S., Pioline Boris (Article) Publié: Journal Of High Energy Physics, vol. p.112 (2012) Texte intégral en Openaccess : Ref HAL: hal-00705850_v1 Ref Arxiv: 1206.1341 DOI: 10.1007/JHEP08(2012)112 WoS: 000309883200057 Ref. & Cit.: NASA ADS Exporter : BibTex | endNote 17 Citations Résumé: In type IIB string compactifications on a Calabi-Yau threefold, the hypermultiplet moduli space $M_H$ must carry an isometric action of the modular group SL(2,Z), inherited from the S-duality symmetry of type IIB string theory in ten dimensions. We investigate how this modular symmetry is realized at the level of the twistor space of $M_H$, and construct a general class of SL(2,Z)-invariant quaternion-Kahler metrics with two commuting isometries, parametrized by a suitably covariant family of holomorphic transition functions. This family should include $M_H$ corrected by D3-D1-D(-1)-instantons (with fivebrane corrections ignored) and, after taking a suitable rigid limit, the Coulomb branch of five-dimensional N=2 gauge theories compactified on a torus, including monopole string instantons. These results allow us to considerably simplify the derivation of the mirror map between type IIA and IIB fields in the sector where only D1-D(-1)-instantons are retained. Commentaires: 29 pages, 1 figure |