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arXiv · 0712.3755

The critical line from imaginary to real baryonic chemical potentials in two-color QCD

Paolo Cea·Leonardo Cosmai·Massimo D'Elia·Alessandro Papa
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Abstract

The method of analytic continuation from imaginary to real chemical potentials $μ$ is one of the few available techniques to study QCD at finite temperature and baryon density. One of its most appealing applications is the determination of the critical line for small $μ$: we perform a direct test of the validity of the method in this case by studying two-color QCD, where the sign problem is absent. The (pseudo)critical line is found to be analytic around $μ^2 = 0$, but a very large precision would be needed at imaginary $μ$ to correctly predict the location of the critical line at real $μ$.

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Paolo Cea, Leonardo Cosmai, Massimo D'Elia, Alessandro Papa. 2008-01-31. The critical line from imaginary to real baryonic chemical potentials in two-color QCD. https://doi.org/10.1103/physrevd.77.051501

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