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arXiv · hep-th/9210147

Renormalization of Tamm-Dancoff Integral Equations

Brett van de Sande·Stephen Pinsky
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Abstract

During the last few years, interest has arisen in using light-front Tamm-Dancoff field theory to describe relativistic bound states for theories such as QCD. Unfortunately, difficult renormalization problems stand in the way. We introduce a general, non-perturbative approach to renormalization that is well suited for the ultraviolet and, presumably, the infrared divergences found in these systems. We reexpress the renormalization problem in terms of a set of coupled inhomogeneous integral equations, the ``counterterm equation.'' The solution of this equation provides a kernel for the Tamm-Dancoff integral equations which generates states that are independent of any cutoffs. We also introduce a Rayleigh-Ritz approach to numerical solution of the counterterm equation. Using our approach to renormalization, we examine several ultraviolet divergent models. Finally, we use the Rayleigh-Ritz approach to find the counterterms in terms of allowed operators of a theory.

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Brett van de Sande, Stephen Pinsky. 1992-10-28. Renormalization of Tamm-Dancoff Integral Equations. https://doi.org/10.1103/physrevd.46.5479

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