Physics Letters B (Sep 2016)

Shear viscosities of photons in strongly coupled plasmas

  • Di-Lun Yang,
  • Berndt Müller

DOI
https://doi.org/10.1016/j.physletb.2016.07.034
Journal volume & issue
Vol. 760, no. C
pp. 565 – 570

Abstract

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We investigate the shear viscosity of thermalized photons in the quark gluon plasma (QGP) at weak coupling and N=4 super Yang–Mills plasma (SYMP) at both strong and weak couplings. We find that the shear viscosity due to the photon–parton scattering up to the leading order of electromagnetic coupling is suppressed when the coupling of the QGP/SYMP is increased, which stems from the blue-shift of the thermal-photon spectrum at strong coupling. In addition, the shear viscosity rapidly increases near the deconfinement transition in a phenomenological model analogous to the QGP.