Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: On statistics and 1/f noise of Brownian motion in Boltzmann-Grad gas and
  finite gas on torus. I. Infinite gas   An attempt is made to compare statistical properties of self-diffusion of
particles constituting gases in infinite volume and on torus. In this first
part, equations are derived which represent roughened but solvable variant of
the collisional approximation to exact BBGKY equations. With their help,
statistics of Brownian motion in infinite gas is considered, under the
Boltzmann-Grad limit, and shown to be essentially non-Gaussian, involving 1/f
fluctuations in diffusivity.

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The categories of this paper are: nlin
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The categories of this paper are: quant-ph
3
The categories of this paper are: physics
11
The categories of this paper are: hep-lat
26
The categories of this paper are: bayes-an
24
The categories of this paper are: dg-ga
14
The categories of this paper are: math-ph
6
The categories of this paper are: astro-ph
31
The categories of this paper are: ao-sci
34
The categories of this paper are: chem-ph
23
The categories of this paper are: solv-int
32
The categories of this paper are: atom-ph
25
The categories of this paper are: patt-sol
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The categories of this paper are: chao-dyn
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The categories of this paper are: alg-geom
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The categories of this paper are: gr-qc