Suprathermal viscosity of dense matter

Alford M., Mahmoodifar S., Schwenzer K. O.

International Workshop on Quantum Chromodynamics: Theory and Experiment, Martina Franca, Italy, 20 - 23 June 2010, vol.1317, pp.380-387 identifier identifier

  • Publication Type: Conference Paper / Full Text
  • Volume: 1317
  • Doi Number: 10.1063/1.3536589
  • City: Martina Franca
  • Country: Italy
  • Page Numbers: pp.380-387
  • Istanbul University Affiliated: No


Motivated by the existence of unstable modes of compact stars that eventually grow large, we study the bulk viscosity of dense matter, taking into account non-linear effects arising in the large amplitude regime, where the deviation mu(Delta) of the chemical potentials from chemical equilibrium fulfills mu(Delta) greater than or similar to T. We find that this supra-thermal bulk viscosity can provide a potential mechanism for saturating unstable modes in compact stars since the viscosity is strongly enhanced. Our study confirms previous results on strange quark matter and shows that the suprathermal enhancement is even stronger in the case of hadronic matter. We also comment on the competition of different weak channels and the presence of suprathermal effects in various color superconducting phases of dense quark matter.