Hydrodynamization times of a holographic fluid far from equilibrium

Journal Article · 13 February 2022 · Physical Review. D.

DOI: https://doi.org/10.1103/physrevd.105.046009 · OSTI ID:1980033

Rougemont, Romulo  ^[1]; Barreto, Willians ^[2]; Noronha, Jorge  ^[3]

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1. Universidade do Estado do Rio de Janeiro (Brazil); OSTI
2. Universidade Federal do ABC, Sao Paulo (Brazil); Universidad de Los Andes, Mérida (Venezuela)
3. University of Illinois at Urbana-Champaign, IL (United States)

Here we investigate several hydrodynamization times for an ensemble of different far-from-equilibrium solutions of the strongly coupled $$\mathscr{N}$$ = 4 supersymmetric Yang-Mills plasma undergoing Bjorken flow. For the ensemble of initial data analyzed in the present work, we find that, with typical tolerances between 3% to 5%, the average hydrodynamization time associated with the late time convergence of the pressure anisotropy to the corresponding Borel resummed hydrodynamic attractor is approximately equal to the average hydrodynamization time associated with the Navier-Stokes result, while both are shorter than the average hydrodynamization time associated with second-order hydrodynamics. On the other hand, we find that the entropy density of the different solutions coalesces to second-order hydrodynamics long before entering in the Navier-Stokes regime. A clear hierarchy between the different average hydrodynamization times of the Bjorken expanding fluid is established for the set of analyzed initial data, comprising also some solutions which, whilst satisfying the dominant and the weak energy conditions at the initial time, evolve such as to transiently violate one or both conditions when the fluid is still far from equilibrium. In particular, solutions violating the weak energy condition are generally found to take a longer time to enter in the hydrodynamic regime than the other solutions.

• Research Organization: University of Illinois at Urbana-Champaign, IL (United States)
• Sponsoring Organization: Fundacao Carlos Chagas Filho de Amparo a Pesquisa do Estado do Rio de Janeiro (FAPERJ); Fundacao de Amparo `a Pesquisa do Estado de S~ao Paulo (FAPESP); USDOE; USDOE Office of Science (SC), Nuclear Physics (NP); Universidade do Estado do Rio de Janeiro (UERJ)
• Grant/Contract Number: SC0021301
• OSTI ID: 1980033
• Journal Information: Physical Review. D., Journal Name: Physical Review. D. Journal Issue: 4 Vol. 105; ISSN 2470-0010
• Publisher: American Physical Society (APS)Copyright Statement
• Country of Publication: United States
• Language: English