Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The Distribution of Redshifts in New Samples of Quasi-stellar Objects   Two new samples of QSOs have been constructed from recent surveys to test the
hypothesis that the redshift distribution of bright QSOs is periodic in
$\log(1+z)$. The first of these comprises 57 different redshifts among all
known close pairs or multiple QSOs, with image separations $\leq$ 10\arcsec,
and the second consists of 39 QSOs selected through their X-ray emission and
their proximity to bright comparatively nearby active galaxies. The redshift
distributions of the samples are found to exhibit distinct peaks with a
periodic separation of $\sim 0.089 $ in $\log(1+z)$ identical to that claimed
in earlier samples but now extended out to higher redshift peaks $z = 2.63,
3.45$ and 4.47, predicted by the formula but never seen before. The periodicity
is also seen in a third sample, the 78 QSOs of the 3C and 3CR catalogues. It is
present in these three datasets at an overall significance level $10^{-5}$ -
$10^{-6}$, and appears not to be explicable by spectroscopic or similar
selection effects. Possible interpretations are briefly discussed.

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The categories of this paper are: nlin
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The categories of this paper are: stat
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The categories of this paper are: hep-th
5
The categories of this paper are: gr-qc
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The categories of this paper are: chao-dyn
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The categories of this paper are: hep-lat
4
The categories of this paper are: cond-mat
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The categories of this paper are: q-alg
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The categories of this paper are: quant-ph
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The categories of this paper are: alg-geom
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The categories of this paper are: comp-gas
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The categories of this paper are: atom-ph
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The categories of this paper are: physics
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The categories of this paper are: mtrl-th
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The categories of this paper are: math-ph
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The categories of this paper are: plasm-ph