Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Nonrational del Pezzo fibrations admitting an action of the Klein simple
  group   We present a series of del Pezzo fibrations of degree $2$ admitting an action
of the Klein simple group and prove their nonrationality by the reduction
modulo $p$ method of Koll\'{a}r. This is relevant to embeddings of the Klein
simple group into the Cremona group of rank $3$.

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The categories of this paper are: adap-org
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The categories of this paper are: nucl-th
28
The categories of this paper are: alg-geom
5
The categories of this paper are: gr-qc
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The categories of this paper are: eess
31
The categories of this paper are: ao-sci
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The categories of this paper are: econ
15
The categories of this paper are: nucl-ex
0
The categories of this paper are: hep-ph
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The categories of this paper are: hep-ex
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The categories of this paper are: supr-con
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The categories of this paper are: stat
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The categories of this paper are: chem-ph
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The categories of this paper are: hep-lat
33
The categories of this paper are: plasm-ph
6
The categories of this paper are: astro-ph