Short-Lived Lattice Quasiparticles for Strongly Interacting Fluids

Entropy

Miller Mendoza Jimenez¹  Sauro Succi² 

[1] ETH Zürich, Computational Physics for Engineering Materials, Institute for Building Materials, Wolfgang-Pauli-Strasse 27, HIT, CH-8093 Zürich, Switzerland;Istituto per le Applicazioni del Calcolo C.N.R., Via dei Taurini 19, 00185 Rome, Italy

关键词: strongly coupled fluids;    Lattice Boltzmann;    quantum fluids;   

DOI  :  10.3390/e17096169

来源: mdpi

【 摘 要 】

It is shown that lattice kinetic theory based on short-lived quasiparticles proves very effective in simulating the complex dynamics of strongly interacting fluids (SIF). In particular, it is pointed out that the shear viscosity of lattice fluids is the sum of two contributions, one due to the usual interactions between particles (collision viscosity) and the other due to the interaction with the discrete lattice (propagation viscosity). Since the latter is negative, the sum may turn out to be orders of magnitude smaller than each of the two contributions separately, thus providing a mechanism to access SIF regimes at ordinary values of the collisional viscosity. This concept, as applied to quantum superfluids in one-dimensional optical lattices, is shown to reproduce shear viscosities consistent with the AdS-CFT holographic bound on the viscosity/entropy ratio. This shows that lattice kinetic theory continues to hold for strongly coupled hydrodynamic regimes where continuum kinetic theory may no longer be applicable.

【 授权许可】

CC BY   
© 2015 by the authors; licensee MDPI, Basel, Switzerland.