Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: A gauge covariant approximation to QED   We examine the Dyson-Schwinger equation for the fermion propagator in
quenched QED in three and four dimension based on spectral representation with
vertex ansatz which preserves Ward-Takahashi Identity.An appropriate
renormalization within dispersion integral smoothes the threshold behaviour of
the fermion self energy in three dimension.Thus we avoid the infrared
singurality in three dimension.The behaviour of the fermion propagator in three
dimension near the threshold is then found to be similar to the four
dimensional one.There exisit analytic solutions for arbitrary gauges and the
full propagators are expressed in terms of hypergeometric function in four
dimension.There is a possibility of dynamical chiral symmetry breaking in four
dimension with vanishing bare mass.

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The categories of this paper are: eess
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The categories of this paper are: plasm-ph
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The categories of this paper are: cmp-lg
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The categories of this paper are: patt-sol
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The categories of this paper are: solv-int
4
The categories of this paper are: cond-mat
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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: quant-ph
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The categories of this paper are: cs
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The categories of this paper are: stat
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The categories of this paper are: adap-org
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The categories of this paper are: math-ph
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The categories of this paper are: nucl-ex
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The categories of this paper are: physics
10
The categories of this paper are: q-bio