Positivity of QCD at asymptotic density

Deog Ki Hong

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arXiv · hep-ph/0301125

Positivity of QCD at asymptotic density

Deog Ki Hong

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Abstract

In this talk, I try to show that the sign problem of dense QCD is due to modes whose frequency is higher than the chemical potential. An effective theory of quasi-quarks near the Fermi surface has a positive measure in the leading order. The higher-order corrections make the measure complex, but they are suppressed as long as the chemical potential is sufficiently larger than $Λ_{\rm QCD}$. As a consequence of the positivity of the effective theory, we can show that the global vector symmetries except the U(1) baryon number are unbroken at asymptotic density.

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Deog Ki Hong. 2003-01-17. Positivity of QCD at asymptotic density. https://arxiv.org/abs/hep-ph/0301125

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