Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: On Infinite-Dimensional Algebras of Symmetries of the Self-Dual
  Yang-Mills Equations   Infinite-dimensional algebras of hidden symmetries of the self-dual
Yang-Mills equations are considered. A current-type algebra of symmetries and
an affine extension of conformal symmetries introduced recently are discussed
using the twistor picture. It is shown that the extended conformal symmetries
of the self-dual Yang-Mills equations have a simple description in terms of
Ward's twistor construction.

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The categories of this paper are: dg-ga
4
The categories of this paper are: cond-mat
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The categories of this paper are: quant-ph
8
The categories of this paper are: hep-ex
18
The categories of this paper are: econ
25
The categories of this paper are: patt-sol
15
The categories of this paper are: nucl-ex
1
The categories of this paper are: cs
36
The categories of this paper are: cmp-lg
33
The categories of this paper are: plasm-ph
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The categories of this paper are: acc-phys
35
The categories of this paper are: mtrl-th
32
The categories of this paper are: atom-ph
29
The categories of this paper are: funct-an
12
The categories of this paper are: nucl-th
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The categories of this paper are: alg-geom