Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Background Symmetries In Orbifolds With Discrete Wilson Lines   Target space symmetries are studied for orbifold compactified string theories
containing Wilson line background fields. The symmetries determined are for
those moduli which contribute to the string loop threshold corrections of the
gauge coupling constants. The groups found are subgroups of the modular group
$PSL(2, Z)$ and depend on the choice of discrete Wilson lines and the shape of
the underlying six-dimensional lattice.

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The categories of this paper are: eess
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The categories of this paper are: q-fin
10
The categories of this paper are: q-bio
25
The categories of this paper are: patt-sol
31
The categories of this paper are: ao-sci
9
The categories of this paper are: nlin
28
The categories of this paper are: alg-geom
13
The categories of this paper are: quant-ph
3
The categories of this paper are: physics
6
The categories of this paper are: astro-ph
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The categories of this paper are: atom-ph
30
The categories of this paper are: q-alg
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The categories of this paper are: cmp-lg
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The categories of this paper are: adap-org
4
The categories of this paper are: cond-mat
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The categories of this paper are: funct-an