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Five-Brane BPS States in Heterotic M-Theory

Antonella Grassi·Zachary Guralnik·Burt Ovrut
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Abstract

We present explicit methods for computing the discriminant curves and the associated Kodaira type fiber degeneracies of elliptically fibered Calabi-Yau threefolds. These methods are applied to a specific three-family, SU(5) grand unified theory of particle physics within the context of Heterotic M-Theory. It is demonstrated that there is always a region of moduli space where a bulk space five-brane is wrapped on a pure fiber in the Calabi-Yau threefold. Restricting the discussion to the smooth parts of the discriminant curve, we explore the properties of the N=2 BPS supermultiplets that arise on the worldvolume of this five-brane due to the degeneration of the elliptic fiber. The associated degenerating M membranes are shown to project to string junctions in the base space. We use string junction techniques to explicitly compute the light BPS hyper- and vector multiplet spectrum for each Kodaira type fiber near the smooth part of the discriminant curve in the SU(5) GUT theory.

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Antonella Grassi, Zachary Guralnik, Burt Ovrut. 2000-09-07. Five-Brane BPS States in Heterotic M-Theory. https://doi.org/10.1088/1126-6708%2F2001%2F01%2F037

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