Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Impurity Green's function of a one-dimensional Fermi-gas   We consider a one-dimensional gas of spin-1/2 fermions interacting through
$\delta$-function repulsive potential of an arbitrary strength. For the case of
all fermions but one having spin up, we calculate time-dependent two-point
correlation function of the spin-down fermion. This impurity Green's function
is represented in the thermodynamic limit as an integral of Fredholm
determinants of integrable linear integral operators.

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The categories of this paper are: dg-ga
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The categories of this paper are: q-alg
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The categories of this paper are: econ
0
The categories of this paper are: hep-ph
34
The categories of this paper are: chem-ph
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The categories of this paper are: adap-org
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The categories of this paper are: eess
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The categories of this paper are: cmp-lg
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The categories of this paper are: comp-gas
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The categories of this paper are: nucl-th
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The categories of this paper are: chao-dyn
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The categories of this paper are: astro-ph
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The categories of this paper are: q-bio
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The categories of this paper are: supr-con
7
The categories of this paper are: hep-th
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The categories of this paper are: bayes-an