Bulk viscosity and the conformal anomaly in the pion gas.
نویسندگان
چکیده
We calculate the bulk viscosity of the massive pion gas within unitarized chiral perturbation theory. We obtain a low-temperature peak arising from explicit conformal breaking due to the pion mass and another peak near the critical temperature, dominated by the conformal anomaly through gluon condensate terms. The correlation between bulk viscosity and conformal breaking supports a recent QCD proposal. We discuss the role of resonances, heavier states, and large-N_(c) counting.
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ورودعنوان ژورنال:
- Physical review letters
دوره 102 12 شماره
صفحات -
تاریخ انتشار 2009