Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Pulsars: Cosmic Permanent 'Neutromagnets'?   We argue that pulsars may be spin-polarized neutron stars, i.e. cosmic
permanent magnets. This would simply explain several observational facts about
pulsars, including the 'beacon effect' itself i.e. the static/stable
misalignment of rotational and magnetic axes, the extreme temporal stability of
the pulses and the existence of an upper limit for the magnetic field strength
- coinciding with the one observed in "magnetars". Although our model
admittedly is speculative, this latter fact seems to us unlikely to be pure
coincidence.

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The categories of this paper are: adap-org
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The categories of this paper are: acc-phys
31
The categories of this paper are: ao-sci
1
The categories of this paper are: cs
25
The categories of this paper are: patt-sol
10
The categories of this paper are: q-bio
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The categories of this paper are: cond-mat
5
The categories of this paper are: gr-qc
3
The categories of this paper are: physics
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The categories of this paper are: nucl-ex
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The categories of this paper are: bayes-an
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The categories of this paper are: q-fin
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The categories of this paper are: comp-gas
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The categories of this paper are: mtrl-th
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The categories of this paper are: q-alg
14
The categories of this paper are: math-ph