منابع مشابه
Nearly perfect fluidity
Shear viscosity is a measure of the amount of dissipation in a simple fluid. In kinetic theory shear viscosity is related to the rate of momentum transport by quasi-particles, and the uncertainty relation suggests that the ratio of shear viscosity η to entropy density s in units of h̄/kB is bounded by a constant. Here, h̄ is Planck’s constant and kB is Boltzmann’s constant. A specific bound has b...
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Perfect fluids are characterized as having the smallest ratio of shear viscosity to entropy density, η/s, consistent with quantum uncertainty and causality. So far, nearly perfect fluids have only been observed in the quark-gluon plasma and in unitary atomic Fermi gases, exotic systems that are amongst the hottest and coldest objects in the known universe, respectively. We use angle resolved ph...
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Experimental results obtained at the Relativistic Heavy Ion Collider (RHIC) have been interpreted in terms of a strongly interacting quark gluon plasma. The strongly interacting plasma is characterized by “perfect fluidity”, i.e. a ratio of shear viscosity to entropy density that saturates a proposed lower bound. In this contribution we explore the possibility that a similar phenomenon takes pl...
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Hydrodynamics and collision-dominated transport are crucial to understand the slow dynamics of many correlated quantum liquids. The ratio eta/s of the shear viscosity eta to the entropy density s is uniquely suited to determine how strongly the excitations in a quantum fluid interact. We determine eta/s in clean undoped graphene using a quantum kinetic theory. As a result of the quantum critica...
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ژورنال
عنوان ژورنال: Physics
سال: 2009
ISSN: 1943-2879
DOI: 10.1103/physics.2.88