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arXiv · hep-lat/0309103

Positivity and Fermionic Dense Matter

Deog Ki Hong·Stephen D. H. Hsu
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Abstract

Euclidean dense matter generically suffers from the fermion sign problem. However, we argue that the sign problem is absent if one considers only low-energy degrees of freedom. Specifically, the low energy effective theory of dense QCD has positive Euclidean path integral measure, which allows one to establish rigorous inequalities showing that the color-flavor locked (CFL) phase is the true vacuum of three flavor, massless QCD. We then describe a method for simulating dense QCD on the lattice. We also discuss applications to electronic systems in condensed matter, such as generalized Hubbard models.

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Deog Ki Hong, Stephen D. H. Hsu. 2003-09-16. Positivity and Fermionic Dense Matter. https://arxiv.org/abs/hep-lat/0309103

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