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The Continuum Version of ϕ^4_{1+1}-theory in Light-Front Quantization

Pierre Grangé·Peter Ullrich·Ernst Werner
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Abstract

A genuine continuum treatment of the massive ϕ^4_{1+1}-theory in light-cone quantization is proposed. Fields are treated as operator valued distributions thereby leading to a mathematically well defined handling of ultraviolet and light cone induced infrared divergences and of their renormalization. Although non-perturbative the continuum light cone approach is no more complex than usual perturbation theory in lowest order. Relative to discretized light cone quantization, the critical coupling increases by 30% to a value r = 1.5. Conventional perturbation theory at the corresponding order yields r_1=1, whereas the RG improved fourth order result is r_4 = 1.8 +-0.05.

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Pierre Grangé, Peter Ullrich, Ernst Werner. 1997-09-23. The Continuum Version of ϕ^4_{1+1}-theory in Light-Front Quantization. https://doi.org/10.1103/physrevd.57.4981

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