Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Infinite-dimensional algebras in dimensionally reduced string theory   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
K\"ahler 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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The categories of this paper are: alg-geom
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The categories of this paper are: comp-gas
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The categories of this paper are: nucl-ex
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The categories of this paper are: stat
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The categories of this paper are: acc-phys
30
The categories of this paper are: q-alg
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The categories of this paper are: nlin
29
The categories of this paper are: funct-an
4
The categories of this paper are: cond-mat
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The categories of this paper are: astro-ph
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The categories of this paper are: econ
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The categories of this paper are: hep-lat
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The categories of this paper are: ao-sci
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The categories of this paper are: patt-sol
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The categories of this paper are: plasm-ph
3
The categories of this paper are: physics