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arXiv · hep-lat/0310046

Phase Fluctuation of Fermion Determinant in Lattice QCD at Finite Density

Y. Sasai·A. Nakamura·T. Takaishi
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Abstract

Once the quark chemical potential $μ$ is introduced in finite density QCD, the fermion determinant appeared in the path integral measure becomes complex. In order to investigate the phase effect of SU(3) lattice QCD (2-flavors), we calculated the fluctuation of the phase of $\detΔ(μ)$ on a $8^3\times4$ lattice at $μ= 0.1$ and 0.2. Then we calculated the chiral condensate and Polyakov line in the no phase and reweighted cases. There is little difference between these two cases at $μ= 0.1$ and 0.2. We consider a possible reason for this result below $μ\le 0.27$ in terms of $Z_3$ symmetry.

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Y. Sasai, A. Nakamura, T. Takaishi. 2003-10-18. Phase Fluctuation of Fermion Determinant in Lattice QCD at Finite Density. https://doi.org/10.1016/s0920-5632(03)02634-3

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