Eur. Phys. J. C (2016) 76: 569
https://doi.org/10.1140/epjc/s10052-016-4412-2

Regular Article - Theoretical Physics

Anatomy of the sign-problem in heavy-dense QCD

¹ Centre for Mathematical Sciences, Plymouth University, Plymouth, PL4 8AA, UK
² Theoretical Physics Division, Department of Mathematical Sciences, University of Liverpool, Liverpool, L69 3BX, UK

^* e-mail: nicolas.garron@plymouth.ac.uk

Received: 24 May 2016
Accepted: 30 September 2016
Published online: 21 October 2016

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.