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arXiv · hep-lat/9604003

Random matrix model of QCD at finite density and the nature of the quenched limit

M. A. Stephanov
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Abstract

We use a random matrix model to study chiral symmetry breaking in QCD at finite chemical potential $μ$. We solve the model and compute the eigenvalue density of the Dirac matrix on a complex plane. A naive ``replica trick'' fails for $μ\neq0$: we find that quenched QCD is not a simple $n\to0$ limit of QCD with $n$ quarks. It is the limit of a theory with $2n$ quarks: $n$ quarks with original action and $n$ quarks with conjugate action. The results agree with earlier studies of lattice QCD at $μ\neq0$ and provide a simple analytical explanation of a long-standing puzzle.

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BibTeXRIS

M. A. Stephanov. 1996-05-14. Random matrix model of QCD at finite density and the nature of the quenched limit. https://doi.org/10.1103/physrevlett.76.4472

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