Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: K-homology and index theory on contact manifolds   Let X be a closed connected contact manifold. On X there is a naturally
arising class of hypoelliptic (but not elliptic) operators which are Fredholm.
In this paper we solve the index problem for this class of operators. The
solution is achieved by combining Van Erp's earlier partial result with the
Baum-Douglas isomorphism of analytic and geometric K-homology.

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The categories of this paper are: cond-mat
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The categories of this paper are: solv-int
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The categories of this paper are: physics
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The categories of this paper are: alg-geom
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The categories of this paper are: q-alg
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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: atom-ph
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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: dg-ga
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The categories of this paper are: cmp-lg
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The categories of this paper are: astro-ph
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The categories of this paper are: math-ph
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The categories of this paper are: hep-lat