Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Connected components of representation spaces of non-orientable surfaces   Let M be a compact closed non-orientable surface. We show that the space of
representations of the fundamental group of M into PSL(2,R) has exactly two
connected components. These two components are the preimages of a certain
Stiefel-Whitney characteristic class, computed in a similar way as the Euler
class in the orientable case.

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The categories of this paper are: ao-sci
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The categories of this paper are: physics
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The categories of this paper are: math-ph
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The categories of this paper are: solv-int
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The categories of this paper are: eess
0
The categories of this paper are: hep-ph
10
The categories of this paper are: q-bio
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The categories of this paper are: dg-ga
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The categories of this paper are: atom-ph
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The categories of this paper are: chem-ph
16
The categories of this paper are: stat
20
The categories of this paper are: acc-phys
9
The categories of this paper are: nlin
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The categories of this paper are: supr-con
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The categories of this paper are: econ
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The categories of this paper are: funct-an