Relativistic Fluid Dynamics In and Out of Equilibrium -- Ten Years of Progress in Theory and Numerical Simulations of Nuclear Collisions

Abstract

Ten years ago, relativistic viscous fluid dynamics was formulated from first principles in an effective field theory framework, based entirely on the knowledge of symmetries and long-lived degrees of freedom. In the same year, numerical simulations for the matter created in relativistic heavy-ion collision experiments became first available, providing constraints on the shear viscosity in QCD. The field has come a long way since then. We present the current status of the theory of non-equilibrium fluid dynamics in 2017, including the divergence of the fluid dynamic gradient expansion, resurgence, non-equilibrium attractor solutions, the inclusion of thermal fluctuations as well as their relation to microscopic theories. Furthermore, we review the theory basis for numerical fluid dynamics simulations of relativistic nuclear collisions, and comparison of modern simulations to experimental data for nucleus-nucleus, nucleus-proton and proton-proton collisions.

214 pages, 26 figures; uninvited review; v2: typos fixed, references added; v3: more typos fixed, full version available as a book (email for discount)

References in corpus (89)

• Viscosity in Strongly Interacting Quantum Field Theories from Black Hole Physics
• Glauber Modeling in High Energy Nuclear Collisions
• Nonlinear Fluid Dynamics from Gravity
• The equation of state in (2+1)-flavor QCD
• Viscosity Information from Relativistic Nuclear Collisions: How Perfect is the Fluid Observed at RHIC?
• Systematic Measurements of Identified Particle Spectra in pp, d+Au and Au+Au Collisions from STAR
• The QCD equation of state with dynamical quarks
• Elliptic and triangular flow in event-by-event (3+1)D viscous hydrodynamics
• Observation of long-range near-side angular correlations in proton-lead collisions at the LHC
• The QCD transition temperature: results with physical masses in the continuum limit II.
• Viscosity Bound and Causality Violation
• Triangularity and Dipole Asymmetry in Heavy Ion Collisions
• A calculation of the bulk viscosity in SU(3) gluodynamics
• Effect of curvature squared corrections in AdS on the viscosity of the dual gauge theory
• Suppression of elliptic flow in a minimally viscous quark-gluon plasma
• Triangular flow in hydrodynamics and transport theory
• Event-by-event gluon multiplicity, energy density and eccentricities at RHIC and LHC
• Universal Quantum Viscosity in a Unitary Fermi Gas
• Dissipative Dynamics of Highly Anisotropic Systems
• Space-time evolution of bulk QCD matter
• Highly-anisotropic and strongly-dissipative hydrodynamics for early stages of relativistic heavy-ion collisions
• Non-thermal fixed points: effective weak-coupling for strongly correlated systems far from equilibrium
• Dissipative Hydrodynamics and Heavy Ion Collisions
• Bulk viscosity of gauge theory plasma at strong coupling
• Analysis of combined HERA data in the Impact-Parameter dependent Saturation model
• Viscous Cosmology for Early- and Late-Time Universe
• Bulk Viscous Cosmology
• Entropy production in collisions of gravitational shock waves and of heavy ions
• Lattice simulations of real-time quantum fields
• Imprints of fluctuating proton shapes on flow in proton-lead collisions at the LHC
• The stickiness of sound: An absolute lower limit on viscosity and the breakdown of second order relativistic hydrodynamics
• Momentum spectra, anisotropic flow, and ideal fluids
• Eccentric protons? Sensitivity of flow to system size and shape in p+p, p+Pb and Pb+Pb collisions
• Second order hydrodynamic coefficients from kinetic theory
• The anisotropic non-equilibrium hydrodynamic attractor
• Elliptic Flow: A Brief Review
• Energy density of the Glasma
• Resolving disagreement for eta/s in a CFT plasma at finite coupling
• Resolving the HBT Puzzle in Relativistic Heavy Ion Collision
• Pre-equilibrium dilepton production from an anisotropic quark-gluon plasma
• Transport coefficients for bulk viscous evolution in the relaxation time approximation
• Fluid dynamics of out of equilibrium boost invariant plasmas
• Mass ordering of spectra from fragmentation of saturated gluon states in high multiplicity proton-proton collisions
• Far-from-equilibrium attractors and nonlinear dynamical systems approach to the Gubser flow
• On the hydrodynamic attractor of Yang-Mills plasma
• Universality of the saturation scale and the initial eccentricity in heavy ion collisions
• Realistic Transverse Images of the Proton Charge and Magnetic Densities
• Causal Viscous Hydrodynamics for Central Heavy-Ion Collisions II: Meson Spectra and HBT Radii
• Holographic thermalization with radial flow
• Particle spectra and HBT radii for simulated central nuclear collisions of C+C, Al+Al, Cu+Cu, Au+Au, and Pb+Pb from Sqrt(s)=62.4-2760 GeV
• Analytical attractor and the divergence of the slow-roll expansion in relativistic hydrodynamics
• Coupling Relativistic Viscous Hydrodynamics to Boltzmann Descriptions
• Title Quantum Optics and Heavy Ion Physics
• How much entropy is produced in strongly coupled Quark-Gluon Plasma (sQGP) by dissipative effects?
• Thermally Fluctuating Second-Order Viscous Hydrodynamics and Heavy-Ion Collisions
• Schwinger-Keldysh on the lattice: a faster algorithm and its application to field theory
• Holographic Collisions across a Phase Transition
• Relaxation time of a CFT plasma at finite coupling
• Relativistic third-order viscous corrections to the entropy four-current from kinetic theory
• Linearized fluid/gravity correspondence: from shear viscosity to all order hydrodynamics
• Elliptic flow at energies available at the CERN Large Hadron Collider: Comparing heavy-ion data to viscous hydrodynamic predictions
• The Bulk Viscosity of a Pion Gas
• Scaling properties at freeze-out in relativistic heavy ion collisions
• Absence of a local rest frame in far from equilibrium quantum matter
• Hydrodynamic fluctuations and the minimum shear viscosity of the dilute Fermi gas at unitarity
• Second order hydrodynamics of a CFT plasma from boost invariant expansion
• Collective flow in ultrarelativistic ${}^3$He-Au collisions
• Measurements of azimuthal anisotropy and charged-particle multiplicity in $d$$+$Au collisions at $\sqrt{s_{{}_{NN}}}=$200, 62.4, 39, and 19.6 GeV
• Coupled kinetic equations for quarks and gluons in the relaxation time approximation
• Azimuthal Anisotropies at High Momentum from Purely Non-Hydrodynamic Transport
• Constraining the viscous freeze-out distribution function with data obtained at the BNL Relativistic Heavy Ion Collider (RHIC)
• Simulation of Black Hole Collisions in Asymptotically AdS Spacetimes
• Covariant description of kinetic freeze out through a finite space-like layer
• Transverse momentum structure of pair correlations as a signature of collective behavior in small collision systems
• Hydrodynamic tails and a fluctuation bound on the bulk viscosity
• Holographic Heavy-Ion Collisions: Analytic Solutions with Longitudinal Flow, Elliptic Flow and Vorticity
• Second-Order Hydrodynamics and Universality in Non-Conformal Holographic Fluids
• Measurements of mass-dependent azimuthal anisotropy in central $p$$+$Au, $d$$+$Au, and ${}^3$He$+$Au collisions at $\sqrt{s_{{}_{NN}}}=200$ GeV
• Suppression of forward dilepton production from an anisotropic quark-gluon plasma
• Nearly Perfect Fluidity in a High Temperature Superconductor
• Divergence of the Chapman-Enskog expansion in relativistic kinetic theory
• Relativistic fluctuating hydrodynamics with memory functions and colored noises
• Saturation of elliptic flow and shear viscosity
• A unified description of the reaction dynamics from pp to pA to AA collisions
• Cavitation in holographic sQGP
• Two roads to hydrodynamic effective actions: a comparison
• Thermodynamic properties and bulk viscosity near phase transition in the Z(2) and O(4) models
• Analytic structure of nonhydrodynamic modes in kinetic theory
• Reversing a heavy-ion collision

Cited by in corpus (49)

• Heavy Ion Collisions: The Big Picture, and the Big Questions
• Relativistic hydrodynamics for spin-polarized fluids
• Non-dissipative second-order transport, spin, and pseudo-gauge transformations in hydrodynamics
• Holography and hydrodynamics with weakly broken symmetries
• Thermodynamic versus kinetic approach to polarization-vorticity coupling
• Spin polarization evolution in a boost invariant hydrodynamical background
• Relativistic Hydrodynamic Fluctuations
• Holographic Collisions across a Phase Transition
• When the entropy has no maximum: A new perspective on the instability of the first-order theories of dissipation
• Two-particle azimuthal correlations in photonuclear ultraperipheral Pb+Pb collisions at 5.02 TeV with ATLAS
• Nearly isentropic flow at sizeable $\eta /s$
• Fluctuation dynamics in a relativistic fluid with a critical point
• Exploring New Small System Geometries in Heavy Ion Collisions
• A numerical exploration of first-order relativistic hydrodynamics
• Non-conformal attractor in boost-invariant plasmas
• The coset construction for non-equilibrium systems
• Causality of fluid dynamics for high-energy nuclear collisions
• The large proper-time expansion of Yang-Mills plasma as a resurgent transseries
• Measurement of azimuthal anisotropy of muons from charm and bottom hadrons in $pp$ collisions at $\sqrt{s}=13$ TeV with the ATLAS detector
• Transverse momentum and process dependent azimuthal anisotropies in $\sqrt{s_{\mathrm{NN}}}=8.16$ TeV $p$+Pb collisions with the ATLAS detector
• On attractor and fixed points in Bjorken flows
• Modeling general-relativistic plasmas with collisionless moments and dissipative two-fluid magnetohydrodynamics
• Analytical attractor for Bjorken expansion
• Small system studies: A theory overview
• Examination of Flow and Non-Flow Factorization Methods in Small Collision Systems
• Equivalence between first-order causal and stable hydrodynamics and Israel-Stewart theory for boost-invariant systems with a constant relaxation time
• Universal behaviour, transients and attractors in supersymmetric Yang-Mills plasma
• Effects of initial state fluctuations on the mean transverse momentum
• Collectivity in pp from resummed interference effects?
• Long- and short-range correlations and their event-scale dependence in high-multiplicity pp collisions at $\sqrt{\text{s}}=13$ TeV
• Shear transport far from equilibrium via holography
• Fully developed relativistic turbulence
• Pseudorapidity distributions of charged hadrons in xenon-xenon collisions at $\sqrt{s_{\mathrm{NN}}}=$ 5.44 TeV
• Dynamics of critical fluctuations: Theory -- phenomenology -- heavy-ion collisions
• The BEST framework for the search for the QCD critical point and the chiral magnetic effect
• Particle production and flow-like effects in small systems
• Initial conditions of bulk matter in ultrarelativistic nuclear collisions
• A resummed method of moments for the relativistic hydrodynamic expansion
• Hydrodynamic fluctuations and long-time tails in a fluid on an anisotropic background
• Initial conditions for nuclear collisions: theory overview
• Relativistic hydrodynamics with spin
• Measurement of the nuclear modification factor for muons from charm and bottom hadrons in Pb+Pb collisions at 5.02 TeV with the ATLAS detector
• Projecting the likely importance of weak-interaction-driven bulk viscosity in neutron star mergers
• Hydrodynamics with spin --- recent developments
• Two Dimensional Turbulence in a Massless Fluid with a Relativistic Lattice Boltzmann Model
• Dissipative type theories for Bjorken and Gubser flows
• Multicomponent Superfluids and Superconductors in Dense Nuclear and Quark Matter
• Out-of-equilibrium Gubser flow attractors
• Nonlinear Dynamics of Tensor Modes in Conformal Real Relativistic Fluids