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arXiv · hep-th/0212275

Twisted Einstein Tensors and Orbifold Geometry

J. deBoer·M. B. Halpern·C. Helfgott
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Abstract

Following recent advances in the local theory of current-algebraic orbifolds, we study various geometric properties of the general WZW orbifold, the general coset orbifold and a large class of (non-linear) sigma model orbifolds. Phase-space geometry is emphasized for the WZW orbifolds - while for the sigma model orbifolds we construct the corresponding {\it sigma model orbifold action}, which includes the previously-known general WZW orbifold action and general coset orbifold action as special cases. We focus throughout on the {\it twisted Einstein tensors} with diagonal monodromy, including the twisted Einstein metric, the twisted B field and the twisted torsion field of each orbifold sector. Finally, we present strong evidence for a conjectured set of {\it twisted Einstein equations} which should describe those sigma model orbifolds in this class which are also 1-loop conformal.

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J. deBoer, M. B. Halpern, C. Helfgott. 2003-11-05. Twisted Einstein Tensors and Orbifold Geometry. https://doi.org/10.1142/s0217751x03015271

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