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arXiv · 1404.7187

The density of states approach to dense quantum systems

Kurt Langfeld·Biagio Lucini
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Abstract

We develop a first-principle generalised density of state method for studying numerically quantum field theories with a complex action. As a proof of concept, we show that with our approach we can solve numerically the strong sign problem of the $Z_3$ spin model at finite density. Our results are confirmed by standard simulations of the theory dual to the considered model, which is free from a sign problem. Our method opens new perspectives on ab initio simulations of cold dense quantum systems, and in particular of Yang-Mills theories with matter at finite densities, for which Monte Carlo based importance sampling are unable to produce sufficiently accurate results.

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Kurt Langfeld, Biagio Lucini. 2014-04-28. The density of states approach to dense quantum systems. https://doi.org/10.1103/physrevd.90.094502

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