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Second-order Hydrodynamics in Next-to-Leading-Order QCD

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 نشر من قبل Jacopo Ghiglieri
 تاريخ النشر 2018
  مجال البحث
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We compute the hydrodynamic relaxation times $tau_pi$ and $tau_j$ for hot QCD at next-to-leading order in the coupling with kinetic theory. We show that certain dimensionless ratios of second-order to first-order transport coefficients obey bounds which apply whenever a kinetic theory description is possible; the computed values lie somewhat above these bounds. Strongly coupled theories with holographic duals strongly violate these bounds, highlighting their distance from a quasiparticle description.



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