Bulk viscosity and the conformal anomaly in the pion gas
D.Fernandez-Fraile, A.Gomez Nicola
TL;DR
This paper calculates the bulk viscosity of a pion gas, revealing peaks related to conformal breaking at different temperatures, and supports a QCD proposal linking bulk viscosity to conformal anomaly.
Contribution
It introduces a calculation of bulk viscosity in a pion gas using Unitarized Chiral Perturbation Theory, highlighting the role of conformal anomaly and resonances.
Findings
Low temperature peak from explicit conformal breaking due to pion mass
Peak near critical temperature dominated by conformal anomaly
Correlation between bulk viscosity and conformal breaking supports QCD proposal
Abstract
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- counting.
Peer Reviews
No public reviews on file for this paper yet. If you reviewed it on a platform where reviews are public (OpenReview, ICLR, NeurIPS, ICML), you can paste yours below so the community can read it here.
Videos
No videos yet. Explain this paper in a talk, walkthrough, or lecture? Add one.