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Mesons in Light-Front QCD$_{2+1}$: Investigation of a Bloch Effective Hamiltonian

Dipankar Chakrabarti·A. Harindranath
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Abstract

We study the meson sector of 2+1 dimensional light-front QCD using a Bloch effective Hamiltonian in the first non-trivial order. The resulting two dimensional integral equation is converted into a matrix equation and solved numerically. We investigate the efficiency of Gaussian quadrature in achieving the cancellation of linear and logarithmic light-front infrared divergences. The vanishing energy denominator problem which leads to severe infrared divergences in 2+1 dimensions is investigated in detail. Our study indicates that in the context of Fock space based effective Hamiltonian methods to tackle gauge theories in 2+1 dimensions, approaches like similarity renormalization method may be mandatory due to uncanceled infrared divergences caused by the vanishing energy denominator problem. We define and study numerically a reduced model which is relativistic, free from infrared divergences, and exhibits logarithmic confinement. The manifestation and violation of rotational symmetry as a function of the coupling are studied quantitatively.

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Dipankar Chakrabarti, A. Harindranath. 2001-07-23. Mesons in Light-Front QCD$_{2+1}$: Investigation of a Bloch Effective Hamiltonian. https://doi.org/10.1103/physrevd.64.105002

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