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Infrared Behaviour of Propagators and Vertices

Frederick T. Hawes·Pieter Maris·Craig D. Roberts
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Abstract

We elucidate constraints imposed by confinement and dynamical chiral symmetry breaking on the infrared behaviour of the dressed-quark and -gluon propagators, and dressed-quark-gluon vertex. In covariant gauges the dressing of the gluon propagator is completely specified by P(k^2):= 1/[1+Pi(k^2)], where Pi(k^2) is the vacuum polarisation. In the absence of particle-like singularities in the dressed-quark-gluon vertex, extant proposals for the dressed-gluon propagator that manifest P(k^2=0)=0 and Max[P(k^2)]~10 neither confine quarks nor break chiral symmetry dynamically. This class includes all existing estimates of P(k^2) via numerical simulations.

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Frederick T. Hawes, Pieter Maris, Craig D. Roberts. 1998-07-22. Infrared Behaviour of Propagators and Vertices. https://doi.org/10.1016/s0370-2693(98)01105-8

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