Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Morita Equivalence and Spectral Triples on Noncommutative Orbifolds   Let $G$ be a finite group. Noncommutative geometry of unital $G$-algebras is
studied. A geometric structure is determined by a spectral triple on the
crossed product algebra associated with the group action. This structure is to
be viewed as a representative of a noncommutative orbifold. Based on a study of
classical orbifold groupoids, a Morita equivalence for the crossed product
spectral triples is developed. Noncommutative orbifolds are Morita equivalence
classes of the crossed product spectral triples. As a special case of this
Morita theory one can study freeness of the $G$-action on the noncommutative
level. In the case of a free action, the crossed product formalism reduced to
the usual spectral triple formalism on the algebra of $G$-invariant functions.

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The categories of this paper are: nlin
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The categories of this paper are: cmp-lg
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The categories of this paper are: hep-th
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The categories of this paper are: chem-ph
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The categories of this paper are: hep-lat
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The categories of this paper are: chao-dyn
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The categories of this paper are: patt-sol
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The categories of this paper are: quant-ph
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The categories of this paper are: plasm-ph
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The categories of this paper are: stat
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The categories of this paper are: bayes-an
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The categories of this paper are: nucl-ex
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The categories of this paper are: comp-gas
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The categories of this paper are: adap-org
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The categories of this paper are: econ
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The categories of this paper are: cond-mat