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arXiv · hep-ph/9308260

Flow Equations for N Point Functions and Bound States

Ulrich Ellwanger
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Abstract

We discuss the exact renormalization group or flow equation for the effective action and its decomposition into one particle irreducible N point functions. With the help of a truncated flow equation for the four point function we study the bound state problem for scalar fields. A combination of analytic and numerical methods is proposed, which is applied to the Wick-Cutkosky model and a QCD-motivated interaction. We present results for the bound state masses and the Bethe-Salpeter wave function. (Figs. 1-4 attached as separate uuencoded post-script files.)

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Ulrich Ellwanger. 1993-08-13. Flow Equations for N Point Functions and Bound States. https://doi.org/10.1007/bf01555911

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