Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Critical number of fermions in three-dimensional QED   Previous analytical studies of quantum electrodynamics in $2+1$ dimensions
(QED3) have shown the existence of a critical number of fermions for onset of
chiral symmetry breaking, the most known being the value $N_c\approx3.28$
obtained by Nash to $1/N^2$ order in the $1/N$ expansion [16]. This analysis is
reconsidered by solving the Dyson-Schwinger equations for the fermion
propagator and the vertex to show that the more accurate gauge independent
value is $N_c\approx2.85$, and for $N<N_c$ the chiral symmetry is dynamically
broken. An estimate for the value of chiral condensate
$\langle\bar\psi\psi\rangle$ is given for $N=2$. Knowing precise $N_c$ would be
important for comparison between continuum studies and lattice simulations of
QED3.

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The categories of this paper are: econ
26
The categories of this paper are: bayes-an
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The categories of this paper are: math-ph
13
The categories of this paper are: quant-ph
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The categories of this paper are: chem-ph
37
The categories of this paper are: supr-con
23
The categories of this paper are: solv-int
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The categories of this paper are: comp-gas
36
The categories of this paper are: cmp-lg
3
The categories of this paper are: physics
31
The categories of this paper are: ao-sci
20
The categories of this paper are: acc-phys
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The categories of this paper are: astro-ph
30
The categories of this paper are: q-alg
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The categories of this paper are: hep-lat
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The categories of this paper are: eess