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arXiv · hep-th/0109208

Nonperturbative renormalization in a scalar model within Light-Front Dynamics

D. Bernard·Th. Cousin·V. A. Karmanov·J. -F. Mathiot
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Abstract

Within the covariant formulation of Light-Front Dynamics, in a scalar model with the interaction Hamiltonian $H=-gψ^{2}(x)ϕ(x)$, we calculate nonperturbatively the renormalized state vector of a scalar "nucleon" in a truncated Fock space containing the $N$, $Nπ$ and $Nππ$ sectors. The model gives a simple example of non-perturbative renormalization which is carried out numerically. Though the mass renormalization $δm^2$ diverges logarithmically with the cutoff $L$, the Fock components of the "physical" nucleon are stable when $L\to\infty$.

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D. Bernard, Th. Cousin, V. A. Karmanov, J. -F. Mathiot. 2001-09-27. Nonperturbative renormalization in a scalar model within Light-Front Dynamics. https://doi.org/10.1103/physrevd.65.025016

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