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arXiv · 0902.0045

An improved lattice measurement of the critical coupling in phi^4_2 theory

David Schaich·Will Loinaz
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Abstract

We use Monte Carlo simulations to obtain an improved lattice measurement of the critical coupling constant [lambda / mu^2]_crit for the continuum (1 + 1)-dimensional (lambda / 4) phi^4 theory. We find that the critical coupling constant depends logarithmically on the lattice coupling, resulting in a continuum value of [lambda / mu^2]_crit = 10.8(1), in considerable disagreement with the previously reported [lambda / mu^2]_crit = 10.26(8). Although this logarithmic behavior was not observed in earlier lattice studies, it is consistent with them, and expected analytically.

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David Schaich, Will Loinaz. 2009-01-31. An improved lattice measurement of the critical coupling in phi^4_2 theory. https://doi.org/10.1103/physrevd.79.056008

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