Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Thurston's norm revisited   We study the Thurston norm on the second homology of a 3-manifold M, which is
the surface bundle over the circle with a pseudo-Anosov monodromy. A novelty of
our approach consists in the application of the C*-algebras to a problem in
topology. Namely, one associates to M a C*-algebra, whose K-theory gives rise
to an algebraic number field K. It is shown, that the trace function on the
ring of integers of K induces a norm on the second homology of M. The norm
coincides with the Thurston norm on the second homology of M.

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The categories of this paper are: patt-sol
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The categories of this paper are: gr-qc
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The categories of this paper are: hep-ex
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The categories of this paper are: adap-org
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The categories of this paper are: chem-ph
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The categories of this paper are: hep-ph
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The categories of this paper are: chao-dyn
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The categories of this paper are: ao-sci
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The categories of this paper are: cs
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The categories of this paper are: q-fin
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The categories of this paper are: hep-th
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The categories of this paper are: solv-int
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The categories of this paper are: nucl-th
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The categories of this paper are: eess
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The categories of this paper are: quant-ph
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The categories of this paper are: bayes-an