Abstract
Standard textbooks will state that hydrodynamics requires near-equilibrium to be applicable. Recently, however, out-of-equilibrium attractor solutions for hydrodynamics have been found in kinetic theory and holography in systems with a high degree of symmetry, suggesting the possibility of a genuine out-of-equilibrium formulation of hydrodynamics. This work demonstrates that attractor solutions also occur in non-conformal kinetic theory and spatially non-homogeneous systems, potentially having important implications for the interpretation of experimental data in heavy-ion and proton-proton collisions and relativistic fluid dynamics as a whole.
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Romatschke, P. Relativistic hydrodynamic attractors with broken symmetries: non-conformal and non-homogeneous. J. High Energ. Phys. 2017, 79 (2017). https://doi.org/10.1007/JHEP12(2017)079
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DOI: https://doi.org/10.1007/JHEP12(2017)079