Viscosity of an ideal relativistic quantum fluid: A perturbative study

Abstract

We show that a quantized ideal fluid will generally exhibit a small but non-zero viscosity due to the backreaction of quantum soundwaves on the background. We use an effective field theory expansion to estimate this viscosity to first order in perturbation theory. We discuss our results, and whether this estimate can be used to obtain a more model-independent estimate of the "quantum bound" on the viscosity of physical systemsComment: Accepted for publication, Phys.Rev.D. Discussion slightly clarified and extended, references added, error in calculation fixed. COnclusions unchange

Hydrodynamic transport coefficients for the non-conformal quark-gluon plasma from holography

“…[126] has recently found that this relation remains valid in a SYM plasma even when the leading order finite t'Hooft coupling corrections are taken into account. 33 The transport coefficients in the theory [127] are known analytically and, even though their numerical values are different than the ones found in this paper (their theory is different than ours), qualitatively they possess the same features found here -ξ5, ξ6 have the same signal as ours and would also display a peak where c…”

“…where D = u µ ∇ µ is the comoving derivative, ∇ α ⊥ = ∆ αβ ∇ β is the derivative transverse to the flow, θ = ∇ µ u µ is the scalar expansion rate, and σ µν = 2∆ αβ µν ∇ α u β is the shear 3 For recent discussions including attempts to formulate dissipative hydrodynamics in terms of an effective action see, for instance, [33][34][35]. 4 Note we use the Landau frame, i.e., uµT µν = −ε u ν [21].…”

Effective field theory of dissipative fluids

“…Recent investigations include [22,[29][30][31][32][33][34][35][36][37][38][39][40][41][42][43][44][45][46][49][50][51]. We will discuss connections to these earlier works along the way.…”

Lagrangian formulation of relativistic Israel-Stewart hydrodynamics

“…Where T 0 is a microscopic scale whose necessity is clear since ∂φ I is dimensionless. The role of this microscopic scale , (which also absorbs a microscopic degeneracy, such as N 2 c in gauge theories) is extensively discussed in [19,23] and will be discussed later in this work.…”