Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Challenge for spontaneous CP violation in Type IIB orientifolds with
  fluxes   We systematically investigate possibilities of realizing the spontaneous CP
violation in Type IIB flux compactifications on toroidal orientifolds. Our
detailed analysis leads to the presence of flat directions at degenerate
CP-breaking and -conserving vacua for a generic choice of three-form fluxes,
indicating that flux compactifications are not sufficient to realize the
spontaneous CP violation. Furthermore, the four-dimensional CP can be embedded
into the duality symmetries, namely modular symmetries for a particular choice
of fluxes.

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The categories of this paper are: hep-ex
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The categories of this paper are: astro-ph
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The categories of this paper are: chao-dyn
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The categories of this paper are: comp-gas
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The categories of this paper are: nlin
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The categories of this paper are: funct-an
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The categories of this paper are: cmp-lg
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The categories of this paper are: alg-geom
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The categories of this paper are: adap-org
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The categories of this paper are: nucl-ex
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The categories of this paper are: dg-ga
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The categories of this paper are: hep-lat
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The categories of this paper are: stat
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The categories of this paper are: acc-phys
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The categories of this paper are: q-fin
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The categories of this paper are: econ