Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Two-loop Euler-Heisenberg effective actions from charged open strings   We present the multiloop partition function of open bosonic string theory in
the presence of a constant gauge field strength, and discuss its low-energy
limit. The result is written in terms of twisted determinants and differentials
on higher-genus Riemann surfaces, for which we provide an explicit
representation in the Schottky parametrization. In the field theory limit, we
recover from the string formula the two-loop Euler-Heisenberg effective action
for adjoint scalars minimally coupled to the background gauge field.

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The categories of this paper are: bayes-an
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The categories of this paper are: supr-con
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The categories of this paper are: q-bio
4
The categories of this paper are: cond-mat
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The categories of this paper are: math-ph
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The categories of this paper are: solv-int
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The categories of this paper are: chao-dyn
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The categories of this paper are: atom-ph
5
The categories of this paper are: gr-qc
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The categories of this paper are: nucl-ex
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The categories of this paper are: ao-sci
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The categories of this paper are: adap-org
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The categories of this paper are: nlin
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The categories of this paper are: alg-geom
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The categories of this paper are: acc-phys
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The categories of this paper are: plasm-ph