Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Acoustic white holes in flowing atomic Bose-Einstein condensates   We study acoustic white holes in a steadily flowing atomic Bose-Einstein
condensate. A white hole configuration is obtained when the flow velocity goes
from a super-sonic value in the upstream region to a sub-sonic one in the
downstream region. The scattering of phonon wavepackets on a white hole horizon
is numerically studied in terms of the Gross-Pitaevskii equation of mean-field
theory: dynamical stability of the acoustic white hole is found, as well as a
signature of a nonlinear back-action of the incident phonon wavepacket onto the
horizon. The correlation pattern of density fluctuations is numerically studied
by means of the truncated-Wigner method which includes quantum fluctuations.
Signatures of the white hole radiation of correlated phonon pairs by the
horizon are characterized; analogies and differences with Hawking radiation
from acoustic black holes are discussed. In particular, a short wavelength
feature is identified in the density correlation function, whose amplitude
steadily grows in time since the formation of the horizon. The numerical
observations are quantitatively interpreted by means of an analytical
Bogoliubov theory of quantum fluctuations for a white hole configuration within
the step-like horizon approximation.

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The categories of this paper are: chem-ph
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The categories of this paper are: atom-ph
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The categories of this paper are: patt-sol
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The categories of this paper are: q-bio
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The categories of this paper are: stat
0
The categories of this paper are: hep-ph
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The categories of this paper are: astro-ph
12
The categories of this paper are: nucl-th
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The categories of this paper are: solv-int
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The categories of this paper are: supr-con
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The categories of this paper are: nlin
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The categories of this paper are: bayes-an
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The categories of this paper are: comp-gas
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The categories of this paper are: cmp-lg
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The categories of this paper are: acc-phys
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The categories of this paper are: chao-dyn