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Non-Commutativity of the Zero Chemical Potential Limit and the Thermodynamic Limit in Finite Density Systems

Jan Ambjorn·Konstantinos N. Anagnostopoulos·Jun Nishimura·Jacobus J. M. Verbaarschot
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Abstract

Monte Carlo simulations of finite density systems are often plagued by the complex action problem. We point out that there exists certain non-commutativity in the zero chemical potential limit and the thermodynamic limit when one tries to study such systems by reweighting techniques. This is demonstrated by explicit calculations in a Random Matrix Theory, which is thought to be a simple qualitative model for finite density QCD. The factorization method allows us to understand how the non-commutativity, which appears at the intermediate steps, cancels in the end results for physical observables.

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Jan Ambjorn, Konstantinos N. Anagnostopoulos, Jun Nishimura, Jacobus J. M. Verbaarschot. 2004-02-25. Non-Commutativity of the Zero Chemical Potential Limit and the Thermodynamic Limit in Finite Density Systems. https://doi.org/10.1103/physrevd.70.035010

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