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arXiv · hep-th/9805088

Dynamical vertex mass generation and chiral symmetry breaking on the light-front

Matthias Burkardt
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Abstract

Naively, helicity flip amplitudes for fermions seem to vanish in the chiral limit of light-front QCD, which would make it nearly impossible to generate a small pion mass in this framework. Using a simple model, it is illustrated how a large helicity flip amplitude is generated dynamically by summing over an infinite number of Fock space components. While the kinetic mass is basically generated by a zero-mode induced counter-term, the vertex mass is generated dynamically by infinitesimally small, but nonzero, momenta. Implications for the renormalization of light-front Hamiltonians for fermions are discussed.

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Matthias Burkardt. 1998-05-14. Dynamical vertex mass generation and chiral symmetry breaking on the light-front. https://doi.org/10.1103/physrevd.58.096015

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