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arXiv · hep-th/9609067

Nonperturbative renormalization group in a light-front three-dimensional real scalar model

Takanori Sugihara·Masanobu Yahiro
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Abstract

The three-dimensional real scalar model, in which the $Z_2$ symmetry spontaneously breaks, is renormalized in a nonperturbative manner based on the Tamm-Dancoff truncation of the Fock space. A critical line is calculated by diagonalizing the Hamiltonian regularized with basis functions. The marginal ($ϕ^6$) coupling dependence of the critical line is weak. In the broken phase the canonical Hamiltonian is tachyonic, so the field is shifted as $ϕ(x)\toφ(x)+v$. The shifted value $v$ is determined as a function of running mass and coupling so that the mass of the ground state vanishes.

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Takanori Sugihara, Masanobu Yahiro. 1996-10-23. Nonperturbative renormalization group in a light-front three-dimensional real scalar model. https://doi.org/10.1103/physrevd.55.2218

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