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arXiv · hep-th/9607131

D-branes and the Conifold Singularity

E. Gava·T. Jayaraman·K. S. Narain·M. H. Sarmadi
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Abstract

We analyze in detail the description of type IIB theory on a Calabi-Yau three-fold near a conifold singularity in terms of intersecting D-branes. In particular we study the singularity structure of higher derivative $F$-terms of the form $F_g W^{2g}$ where $W$ is the gravitational superfield. This singularity is expected to be due to a one -loop contribution from a charged soliton hypermultiplet becoming massless at the conifold point. In the intersecting D-brane description this soliton is described by an open string stretched between the two D-branes. After identifying the graviphoton vertex as a closed string operator we show that $F_g$'s have the expected singularity structure in the limit of vanishing soliton mass.

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E. Gava, T. Jayaraman, K. S. Narain, M. H. Sarmadi. 1996-07-16. D-branes and the Conifold Singularity. https://doi.org/10.1016/0370-2693(96)01128-8

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