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arXiv · 1204.0651

The type of the phase transition and coupling values in \lambda \phi^4 model

M. Bordag·V. Demchik·A. Gulov·V. Skalozub
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Abstract

The temperature induced phase transition is investigated in the one-component scalar field \phi^4 model on the lattice. Using the GPU cluster a huge amount of Monte Carlo simulation data is collected for a wide interval of coupling values. This gives a possibility to determine the low bound on the coupling constant \lambda_0 when the transition happens and investigate its type. We found that for the values of \lambda close to this bound a weak-first-order phase transition takes place. It converts into a second order one with the increase of \lambda. A comparison with the results obtained in analytic and numeric calculations by other authors is given.

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M. Bordag, V. Demchik, A. Gulov, V. Skalozub. 2012-04-03. The type of the phase transition and coupling values in \lambda \phi^4 model. https://doi.org/10.1142/s0217751x12501163

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