Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Conformally flat pseudo Riemannian Homogeneous Ricci Solitons 4 spaces   We consider four dimensional conformally flat homogeneous pseudo Riemannian
manifolds. According to forms (Seger types) of the Ricci operator, we provide a
full classification of four dimensional pseudo Riemannian conformally flat
homogeneous Ricci solitons.

8
The categories of this paper are: hep-ex
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The categories of this paper are: math-ph
35
The categories of this paper are: mtrl-th
6
The categories of this paper are: astro-ph
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The categories of this paper are: adap-org
10
The categories of this paper are: q-bio
15
The categories of this paper are: nucl-ex
18
The categories of this paper are: econ
33
The categories of this paper are: plasm-ph
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The categories of this paper are: chem-ph
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The categories of this paper are: solv-int
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The categories of this paper are: chao-dyn
9
The categories of this paper are: nlin
36
The categories of this paper are: cmp-lg
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The categories of this paper are: patt-sol
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The categories of this paper are: alg-geom