Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Spin-1/2 fermions: crossover from weak to strong attractive interaction   The formation and dissociation of bosonic molecules in an optical lattice,
formed by spin-1/2 fermionic atoms, is considered in the presence of an
attractive nearest-neighbor interaction. A mean-field approximation reveals
three different phases at zero temperature: an empty, a condensate and a
Mott-insulating phase. The density of fermionic atoms and the density of
bosonic molecules indicate a characteristic behavior with respect to the
interaction strength that distinguishes between a dilute and a dense regime. In
particular, the attractive interaction favors the formation of molecules in the
dilute regime and the dissociation of atoms in the dense regime.

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The categories of this paper are: q-fin
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The categories of this paper are: nlin
36
The categories of this paper are: cmp-lg
5
The categories of this paper are: gr-qc
29
The categories of this paper are: funct-an
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The categories of this paper are: stat
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The categories of this paper are: astro-ph
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The categories of this paper are: eess
35
The categories of this paper are: mtrl-th
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The categories of this paper are: quant-ph
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The categories of this paper are: econ
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The categories of this paper are: adap-org
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The categories of this paper are: acc-phys
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The categories of this paper are: chem-ph
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The categories of this paper are: q-alg
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The categories of this paper are: chao-dyn