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arXiv · hep-th/9506205

Infinite-dimensional algebras in dimensionally reduced string theory

Alexandros A. Kehagias
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Abstract

We examine 4-dimensional string backgrounds compactified over a two torus. There exist two alternative effective Lagrangians containing each two $SL(2)/U(1)$ sigma-models. Two of these sigma-models are the complex and the Kähler structures on the torus. The effective Lagrangians are invariant under two different $O(2,2)$ groups and by the successive applications of these groups the affine $\widehat{O}(2,2)$ Kac-Moody is emerged. The latter has also a non-zero central term which generates constant Weyl rescalings of the reduced 2-dimensional background. In addition, there exists a number of discrete symmetries relating the field content of the reduced effective Lagrangians.

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Alexandros A. Kehagias. 1995-06-30. Infinite-dimensional algebras in dimensionally reduced string theory. https://doi.org/10.1016/0370-2693(95)01149-k

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