Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Bogoliubov theory of entanglement in a Bose-Einstein condensate   We consider a Bose-Einstein condensate which is illuminated by a short
resonant light pulse that coherently couples two internal states of the atoms.
We show that the subsequent time evolution prepares the atoms in an interesting
entangled state called a spin squeezed state. This evolution is analysed in
detail by developing a Bogoliubov theory which describes the entanglement of
the atoms. Our calculation is a consistent expansion in $1/\sqrt{N}$, where $N$
is the number of particles in the condensate, and our theory predict that it is
possible to produce spin squeezing by at least a factor of $1/\sqrt{N}$. Within
the Bogoliubov approximation this result is independent of temperature.

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The categories of this paper are: math-ph
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The categories of this paper are: q-alg
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The categories of this paper are: math
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The categories of this paper are: cmp-lg
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The categories of this paper are: funct-an
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The categories of this paper are: alg-geom
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The categories of this paper are: eess
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The categories of this paper are: cs
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The categories of this paper are: hep-ph
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The categories of this paper are: plasm-ph
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The categories of this paper are: chao-dyn
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The categories of this paper are: atom-ph
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The categories of this paper are: bayes-an
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The categories of this paper are: gr-qc
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The categories of this paper are: astro-ph
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The categories of this paper are: physics