Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The nature of the companion of PSR J1719-1438: a white dwarf or an
  exotic object?   We rise in this Letter the possibility that the very dense, compact companion
of PSR J1719-1438, having a Jupiter-like mass is an exotic quark object rather
than a light helium or carbon white dwarf. The exotic hypothesis explains
naturally some of the observed features, and gives quite strong predictions for
this system, to be confirmed or refuted in future feasible studies.

8
The categories of this paper are: hep-ex
28
The categories of this paper are: alg-geom
23
The categories of this paper are: solv-int
2
The categories of this paper are: math
18
The categories of this paper are: econ
31
The categories of this paper are: ao-sci
25
The categories of this paper are: patt-sol
24
The categories of this paper are: dg-ga
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The categories of this paper are: chao-dyn
11
The categories of this paper are: hep-lat
27
The categories of this paper are: comp-gas
20
The categories of this paper are: acc-phys
34
The categories of this paper are: chem-ph
15
The categories of this paper are: nucl-ex
5
The categories of this paper are: gr-qc
30
The categories of this paper are: q-alg