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arXiv · 1206.2954

Lattice study of the Silver Blaze phenomenon for a charged scalar phi-4 field

Christof Gattringer·Thomas Kloiber
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Abstract

We analyze a complex scalar field with phi-4 interaction and a chemical potential mu on the lattice. An exact flux representation of the partition sum is used which avoids the complex action problem and based on a generalized worm algorithm we can run Monte Carlo simulations at arbitrary densities. We study thermodynamical quantities as a function of the chemical potential mu for zero- and finite temperature. It is shown that at zero temperature thermodynamical observables are independent of mu up to a critical value mu_c (Silver Blaze phenomenon). In a spectroscopy calculation we cross-check that mu_c agrees with the mass m of the scalar field. The Silver Blaze region ends in a second order phase transition and we show that for low temperatures the second order phase boundary persists and separates a pseudo Silver Blaze region from a condensed phase with strong mu-dependence.

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Christof Gattringer, Thomas Kloiber. 2017-02-03. Lattice study of the Silver Blaze phenomenon for a charged scalar phi-4 field. https://doi.org/10.1016/j.nuclphysb.2012.12.005

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