Billo, MarcoDenef, FrederikFre, PietroPesando, IgorTroost, WalterVan Proeyen, AntoineZanon, Daniela2009-04-011999Billo, Marco, Frederik Denef, Pietro Fre, Igor Pesando, Walter Troost, Antoine Van Proeyen, and Daniela Zanon. 1999. Special Geometry of Calabi-Yau compactifications near a rigid limit. Fortschritte der Physik 47(1-3): 133-139.0015-82081521-3978http://nrs.harvard.edu/urn-3:HUL.InstRepos:2766344We discuss, in the framework of special Kahler geometry, some aspects of the "rigid limit" of type IIB string theory compactified on a Calabi-Yau threefold. We outline the general idea and demonstrate by direct analysis of a specific example how this limit is obtained. The decoupling of gravity and the reduction of special Kahler geometry from local to rigid is demonstrated explicitly, without first going to a noncompact approximation of the Calabi-Yau. In doing so, we obtain the Seiberg-Witten Riemann surfaces corresponding to different rigid limits as degenerating branches of a higher genus Riemann surface, defined for all values of the moduli. Apart from giving a nice geometrical picture, this allows one to calculate easily some gravitational corrections to e.g. the Seiberg-Witten central charge formula. We make some connections to the 2/5-brane picture, also away from the rigid limit, though only at the formal level.en-US10.1002/(SICI)1521-3978(199901)47:1/3<133::AID-PROP133>3.0.CO;2-3