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arXiv · 1605.02709

Anatomy of the sign-problem in heavy-dense QCD

Nicolas Garron·Kurt Langfeld
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Abstract

QCD at finite densities of heavy quarks is investigated using the density-of-states method. The phase factor expectation value of the quark determinant is calculated to unprecedented precision as a function of the chemical potential. Results are validated using those from a reweighting approach where the latter can produce a significant signal-to-noise ratio. We confirm the particle-hole symmetry at low temperatures, find a strong sign problem at intermediate values of the chemical potential, and an inverse Silver Blaze feature for chemical potentials close to the onset value: here, the phase quenched theory underestimates the density of the full theory.

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Nicolas Garron, Kurt Langfeld. 2016-05-09. Anatomy of the sign-problem in heavy-dense QCD. https://doi.org/10.1140/epjc%2Fs10052-016-4412-2

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