Positivity of Qcd at Asymptotic Density
نویسنده
چکیده
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 higherorder corrections make the measure complex, but they are suppressed as long as the chemical potential is sufficiently larger than ΛQCD. 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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