Hydrodynamization in kinetic theory: Transient modes and the gradient expansion

  title={Hydrodynamization in kinetic theory: Transient modes and the gradient expansion},
  author={Michal P. Heller and Aleksi Kurkela and Michał Spaliński and Viktor Svensson},
  journal={Physical Review D},
We explore the transition to hydrodynamics in a weakly-coupled model of quark-gluon plasma given by kinetic theory in the relaxation time approximation with conformal symmetry. We demonstrate that the gradient expansion in this model has a vanishing radius of convergence due to the presence of a transient (nonhydrodynamic) mode, in a way similar to results obtained earlier in strongly-coupled gauge theories. This suggests that the mechanism by which hydrodynamic behaviour emerges is the same… 

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