Bulk viscosity and relaxation time of causal dissipative relativistic fluid dynamics

Journal Article · Tue Feb 15 00:00:00 EST 2011 · Physical Review. C, Nuclear Physics

DOI:https://doi.org/10.1103/PHYSREVC.83.024906· OSTI ID:21499432

Xuguang, Huang; Rischke, Dirk H ^[1]; Kodama, Takeshi ^[2]; Koide, Tomoi ^[1]

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1. Frankfurt Institute for Advanced Studies, D-60438 Frankfurt am Main (Germany)
2. Instituto de Fisica, Universidade Federal do Rio de Janeiro, Caixa Postale 68528, 21945-970, Rio de Janeiro (Brazil)

The microscopic formulas of the bulk viscosity {zeta} and the corresponding relaxation time {tau}{sub {Pi}} in causal dissipative relativistic fluid dynamics are derived by using the projection operator method. In applying these formulas to the pionic fluid, we find that the renormalizable energy-momentum tensor should be employed to obtain consistent results. In the leading-order approximation in the chiral perturbation theory, the relaxation time is enhanced near the QCD phase transition, and {tau}{sub {Pi}} and {zeta} are related as {tau}{sub {Pi}={zeta}}/[{beta}{l_brace}(1/3-c{sub s}{sup 2})({epsilon}+P)-2({epsilon}-3P)/9{r_brace}], where {epsilon}, P, and c{sub s} are the energy density, pressure, and velocity of sound, respectively. The predicted {zeta} and {tau}{sub {Pi}} should satisfy the so-called causality condition. We compare our result with the results of the kinetic calculation by Israel and Stewart and the string theory, and confirm that all three approaches are consistent with the causality condition.

• OSTI ID: 21499432
• Journal Information: Physical Review. C, Nuclear Physics, Vol. 83, Issue 2; Other Information: DOI: 10.1103/PhysRevC.83.024906; (c) 2011 American Institute of Physics; ISSN 0556-2813
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
73 NUCLEAR PHYSICS AND RADIATION PHYSICS
APPROXIMATIONS
CAUSALITY
CHIRALITY
COMPARATIVE EVALUATIONS
ENERGY DENSITY
ENERGY-MOMENTUM TENSOR
FLUID MECHANICS
FLUIDS
PERTURBATION THEORY
PHASE TRANSFORMATIONS
PROJECTION OPERATORS
QUANTUM CHROMODYNAMICS
RELATIVISTIC RANGE
RELAXATION TIME
SOUND WAVES
STRING MODELS
STRING THEORY
VELOCITY
VISCOSITY
CALCULATION METHODS
COMPOSITE MODELS
ENERGY RANGE
EVALUATION
EXTENDED PARTICLE MODEL
FIELD THEORIES
MATHEMATICAL MODELS
MATHEMATICAL OPERATORS
MECHANICS
M-THEORY
PARTICLE MODELS
PARTICLE PROPERTIES
QUANTUM FIELD THEORY
QUARK MODEL
TENSORS