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arXiv · hep-ph/0008307

Non-perturbative calculations of a global U(1) theory at finite density and temperature

T. S. Evans·H. F. Jones·D. Winder
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Abstract

We use an optimised hopping parameter expansion for the free energy (linear delta expansion) to study the phase transitions at finite temperature and finite charge density in a global U(1) scalar Higgs sector on the lattice at large lattice couplings. We are able to plot out phase diagrams in lattice parameter space and find that the standard second-order phase transition with temperature at zero chemical potential becomes first order as the chemical potential increases.

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T. S. Evans, H. F. Jones, D. Winder. 2000-08-29. Non-perturbative calculations of a global U(1) theory at finite density and temperature. https://doi.org/10.1016/s0550-3213(00)00753-7

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