Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: An action of a Lie algebra on the homology groups of moduli spaces of
  stable sheaves   We construct an action of a Lie algebra on the homology groups of moduli
spaces of stable sheaves on K3 surfaces under some technical conditions. This
is a generalization of Nakajima's construction of sl_2-action on the homology
groups. In particular, for an A,D,E-configulation of (-2)-curves, we shall give
a collection of moduli spaces such that the associated Lie algebra acts on
their homology groups.

18
The categories of this paper are: econ
34
The categories of this paper are: chem-ph
24
The categories of this paper are: dg-ga
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The categories of this paper are: eess
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The categories of this paper are: funct-an
15
The categories of this paper are: nucl-ex
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The categories of this paper are: bayes-an
0
The categories of this paper are: hep-ph
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The categories of this paper are: adap-org
5
The categories of this paper are: gr-qc
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The categories of this paper are: supr-con
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The categories of this paper are: q-alg
12
The categories of this paper are: nucl-th
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The categories of this paper are: patt-sol
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The categories of this paper are: cmp-lg
23
The categories of this paper are: solv-int