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Noncompact Gepner Models for Type II Strings on a Conifold and an ALE Instanton

Shun'ya Mizoguchi
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Abstract

We construct modular invariant partition functions for type II strings on a conifold and a singular Eguchi-Hanson instanton by means of the SL(2,R)/U(1) version of Gepner models. In the conifold case, we find an extra massless hypermultiplet in the IIB spectrum and argue that it may be identified as a soliton. In the Eguchi-Hanson case, our formula is new and different from the earlier result, in particular does not contain graviton. The lightest IIB fields are combined into a six-dimensional (2,0) tensor multiplet with a negative mass square. We give an interpretation to it as a doubleton-like mode.

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Shun'ya Mizoguchi. 2000-10-25. Noncompact Gepner Models for Type II Strings on a Conifold and an ALE Instanton. https://arxiv.org/abs/hep-th/0009240

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