Nonperturbative calculation of Green and vertex functions in terms of particle contours

N. G. Stefanis

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arXiv · hep-th/9607063

Nonperturbative calculation of Green and vertex functions in terms of particle contours

N. G. Stefanis

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Abstract

The infrared regime of fermionic Green and vertex functions is studied analytically within a geometric approach which simulates soft interactions by an {\it effective} theory of contours. Expanding the particle path integral in terms of dominant contours at large distances, all-order results in the coupling constant are obtained for the renormalized fermion propagator and a universal vertex function with physical characteristics close to those associated with the Isgur-Wise function in the weak decays of heavy mesons. The extension to the ultraviolet regime is scetched.

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N. G. Stefanis. 1996-07-08. Nonperturbative calculation of Green and vertex functions in terms of particle contours. https://arxiv.org/abs/hep-th/9607063

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