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arXiv · hep-th/9210076

Gravitational Instantons in Heterotic String Theory: The H-Map and the Moduli Deformations of (4,4) Superconformal Field Theories

M. Billo'·P. Fre'·L. Girardello·A. Zaffaroni
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Abstract

We study the problem of string propagation in a general instanton background for the case of the complete heterotic superstring. We define the concept of generalized HyperK\" ahler manifolds and we relate it to (4,4) superconformal theories. We propose a generalized h-map construction that predicts a universal SU(6) symmetry for the modes of the string excitations moving in an instanton background. We also discuss the role of abstract $N$=4 moduli and, applying it to the particular limit case of the solvable SU(2) X R instanton found by Callan et al. we show that it admits deformations and corresponds to a point in a 16-dimensional moduli space. The geometrical characterization of the other spaces in the same moduli-space remains an outstanding problem.

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M. Billo', P. Fre', L. Girardello, A. Zaffaroni. 1992-11-05. Gravitational Instantons in Heterotic String Theory: The H-Map and the Moduli Deformations of (4,4) Superconformal Field Theories. https://doi.org/10.1142/s0217751x9300093x

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