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arXiv · hep-th/9605222

Resolving Singularities in (0,2) Models

J. Distler·B. Greene·D. Morrison
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Abstract

In contrast to the familiar (2,2) case, the singularities which arise in the (0,2) setting can be associated with degeneration of the base Calabi-Yau manifold {\it and/or}\/ with degenerations of the gauge bundle. We study a variety of such singularities and give a procedure for resolving those which can be cured perturbatively. Among the novel features which emerge are models in which smoothing singularities in the base yields a gauge {\it sheaf}\/ as opposed to a gauge bundle as the structure to which left moving fermions couple. Supersymmetric $σ$-models with target data being an appropriate sheaf on a Calabi-Yau space therefore appear to be the natural arena for N=1 string models in four dimensions. We also indicate a variety of singularities which would require a nonperturbative treatment for their resolution and briefly discuss applications to heterotic models on K3.

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J. Distler, B. Greene, D. Morrison. 1996-05-30. Resolving Singularities in (0,2) Models. https://doi.org/10.1016/s0550-3213(96)90135-2

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