Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Representing homology classes by symplectic surfaces   We derive an obstruction to representing a homology class of a symplectic
4-manifold by an embedded, possibly disconnected, symplectic surface.

36
The categories of this paper are: cmp-lg
24
The categories of this paper are: dg-ga
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The categories of this paper are: alg-geom
15
The categories of this paper are: nucl-ex
33
The categories of this paper are: plasm-ph
21
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: ao-sci
25
The categories of this paper are: patt-sol
8
The categories of this paper are: hep-ex
26
The categories of this paper are: bayes-an
4
The categories of this paper are: cond-mat
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The categories of this paper are: funct-an
18
The categories of this paper are: econ
12
The categories of this paper are: nucl-th
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The categories of this paper are: atom-ph