Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Moduli Dependence of One--Loop Gauge Couplings in (0,2)
  Compactifications   We derive the moduli dependence of the one--loop gauge couplings for
non--vanishing gauge background fields in a four--dimensional heterotic (0,2)
string compactification. Remarkably, these functions turn out to have a
representation as modular functions on an auxiliary Riemann surface on
appropriate truncations of the full moduli space. In particular, a certain kind
of one--loop functions is given by the free energy of two--dimensional solitons
on this surface.

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The categories of this paper are: quant-ph
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The categories of this paper are: funct-an
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The categories of this paper are: chem-ph
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The categories of this paper are: q-fin
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The categories of this paper are: econ
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The categories of this paper are: physics
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The categories of this paper are: astro-ph
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The categories of this paper are: comp-gas
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The categories of this paper are: hep-lat
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The categories of this paper are: q-alg
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The categories of this paper are: ao-sci
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The categories of this paper are: plasm-ph
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The categories of this paper are: cs
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The categories of this paper are: bayes-an
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The categories of this paper are: gr-qc
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The categories of this paper are: eess