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arXiv · hep-lat/0609076

Phase of the Fermion Determinant at Nonzero Chemical Potential

K. Splittorff·J. J. M. Verbaarschot
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Abstract

We show that in the microscopic domain of QCD (also known as the $ε$-domain) at nonzero chemical potential the average phase factor of the fermion determinant is nonzero for $μ< m_π/2$ and is exponentially suppressed for larger values of the chemical potential. This follows from the chiral Lagrangian that describes the low-energy limit of the expectation value of the phase factor. Explicit expressions for the average phase factor are derived using a random matrix formulation of the zero momentum limit of this chiral Lagrangian.

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K. Splittorff, J. J. M. Verbaarschot. 2006-09-29. Phase of the Fermion Determinant at Nonzero Chemical Potential. https://doi.org/10.1103/physrevlett.98.031601

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