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arXiv · hep-lat/0405016

Phase diagram of the lattice Wess-Zumino model from rigorous lower bounds on the energy

Matteo Beccaria·Massimo Campostrini·Gian Fabrizio De Angelis·Alessandra Feo
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Abstract

We study the lattice N=1 Wess-Zumino model in two dimensions and we construct a sequence $ρ^{(L)}$ of exact lower bounds on its ground state energy density $ρ$, converging to $ρ$ in the limit $L\to\infty$. The bounds $ρ^{(L)}$ can be computed numerically on a finite lattice with $L$ sites and can be exploited to discuss dynamical symmetry breaking. The transition point is determined and compared with recent results based on large-scale Green Function Monte Carlo simulations with good agreement.

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Matteo Beccaria, Massimo Campostrini, Gian Fabrizio De Angelis, Alessandra Feo. 2004-05-18. Phase diagram of the lattice Wess-Zumino model from rigorous lower bounds on the energy. https://doi.org/10.1103/physrevd.70.035011

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