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arXiv · hep-lat/9412086

Monte Carlo simulation of $1+1$-dimensional $ϕ^4$ quantum field theory

Wolfhard Janke·Tilman Sauer
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Abstract

We report results of a Monte Carlo simulation of the $ϕ^4$ quantum field theory using multigrid simulation techniques and a refined discretization scheme. The resulting accuracy of our data allows for a significant test of an analytical approximation based on a variational ansatz. While the variational approximation is well reproduced for a large range of parameters we find significant deviations for low temperatures and large couplings.

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Wolfhard Janke, Tilman Sauer. 1994-12-17. Monte Carlo simulation of $1+1$-dimensional $ϕ^4$ quantum field theory. https://doi.org/10.1016/0920-5632(95)00421-5

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