2017/04/16 by M. Martinez, Mauricio Martínez, M. McNelis +2 · 1 citation
Engineering · Mathematics · Physics and Astronomy · #Anisotropy #Boltzmann equation #Classical mechanics #Conservation law #Cosmology and Gravitation Theories #Dissipative system #Distribution function #Equations of motion #Flow (mathematics) #Fluid Dynamics and Turbulent Flows #Fluid dynamics #High-Energy Particle Collisions Research #Mathematical analysis #Mathematical physics #Mathematics #Mechanics #Physics #Quantum mechanics #Statistical physics #nucl-th
paper · pdf · open access · doi:10.1016/j.nuclphysa.2017.04.012
published in Nuclear Physics A 967, 413-416 (Elsevier BV) · 4 pages, 1 Figure. Proceedings of the XXVIth International Conference on Ultrarelativistic Nucleus-Nucleus Collisions (Quark Matter 2017) Chicago, February 6-11, 2017
arxiv created 2017/04/16 · openalex publication_date 2017/09/25 · arxiv updated 2018/03/14 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
In this work we describe the dynamics of a highly anisotropic system undergoing boost-invariant longitudinal and azimuthally symmetric radial expansion (Gubser flow) for arbitrary shear viscosity to entropy density ratio. We derive the equations of motion of dissipative anisotropic hydrodynamics by applying to this situation the moments method recently derived by Molnár et al. (MNR) [E. Molnar, H. Niemi, and D. H. Rischke, “Derivation of anisotropic dissipative fluid dynamics from the Boltzmann equation,” Phys. Rev. D93 no. 11, (2016) 114025, arXiv:1602.00573 [nucl-th], E. Molnar, H. Niemi, and D. H. Rischke, “Closing the equations of motion of anisotropic fluid dynamics by a judicious choice of a moment of the Boltzmann equation,” Phys. Rev. D94 no. 12, (2016) 125003, arXiv:1606.09019 [nucl-th]], based on an expansion around an arbitrary anisotropic one-particle distribution function. One requires an additional evolution equation in order to close the conservation laws. This is achieved by selecting the relaxation equation for the longitudinal pressure with a suitable Landau matching condition. As a result one obtains two coupled differential equations for the energy density and the longitudinal pressure which respect the SO(3)q⊗SO(1,1)⊗Z2 symmetry of the Gubser flow in the deSitter space. These equations are solved numerically and compared with the predictions of the recently found exact solution of the relaxation-time-approximation Boltzmann equation subject to the same flow. We also compare our numerical results with other fluid dynamical models. We observe that the MNR description of anisotropic fluid dynamics reproduces the space-time evolution of the system than all other currently known hydrodynamical approaches.