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Avoiding the boson sign problem at finite chemical potential

Michael G. Endres
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Abstract

The usual path integral formulation for scalar particles at finite density involves a sign problem, making numerical simulation impractical. We present alternative methods free of this difficulty. We apply these approaches to phi^4 theory in 2+1 dimensions, presenting preliminary numerical results for physical quantities in the vicinity of the phase transition in the T-mu plane.

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Michael G. Endres. 2006-09-21. Avoiding the boson sign problem at finite chemical potential. https://arxiv.org/abs/hep-lat/0609037

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