Field redefinition and its impact in relativistic hydrodynamics
arXiv:2409.15387 · doi:10.1103/PhysRevD.111.014034
Abstract
In this paper, we explore the impact of field redefinition on the spectrum of linearized perturbations in relativistic hydrodynamics. We observe that the spectrum of hydrodynamics modes is never affected by the local field redefinition, however, the spectrum of the non-hydrodynamic modes is affected. Through an appropriate all-order redefinition, non-hydrodynamic modes can be eliminated, leading to a new frame where the spectrum contains only hydrodynamic modes. We also observe that the resulting stress-energy tensor may have an infinite series in momentum space, with a convergence radius linked to the eliminated non-hydrodynamic mode. In certain special cases, higher-order terms in the stress-energy tensor under field redefinition may cancel, indicating that non-hydrodynamic modes are mere artefacts of the fluid variable choice and hold no physical significance, even if they appear to violate physical constraints. Using a special toy example, we find a criterion to distinguish between physical and unphysical non-hydrodynamic modes.
Companion paper of arXiv:2410.19015; Accepted version in Physical Review D Journal
References in corpus (28)
- First-order relativistic hydrodynamics is stable
- Causality and existence of solutions of relativistic viscous fluid dynamics with gravity
- Hydrodynamic gradient expansion in gauge theory plasmas
- Nonlinear causality of general first-order relativistic viscous hydrodynamics
- Does stability of relativistic dissipative fluid dynamics imply causality?
- The complex life of hydrodynamic modes
- Stability and Causality in relativistic dissipative hydrodynamics
- On the convergence of the gradient expansion in hydrodynamics
- Holography and hydrodynamics with weakly broken symmetries
- Causality of the Einstein-Israel-Stewart Theory with Bulk Viscosity
- Non-Boost Invariant Fluid Dynamics
- Rigorous bounds on transport from causality
- Absence of a local rest frame in far from equilibrium quantum matter
- Bounds on transport from hydrodynamic stability
- Transient Relativistic Fluid Dynamics in a General Hydrodynamic Frame
- Causality of fluid dynamics for high-energy nuclear collisions
- Hydrodynamic gradient expansion in linear response theory
- Fluctuating relativistic dissipative hydrodynamics as a gauge theory
- Causality and stability in relativistic viscous non-resistive magneto-fluid dynamics
- Convergence of hydrodynamic modes: insights from kinetic theory and holography
- A stable and causal model of magnetohydrodynamics
- A hyperbolic theory of relativistic conformal dissipative fluids
- Hydrodynamics without boosts
- The stochastic relativistic advection diffusion equation from the Metropolis algorithm
- Causality and classical dispersion relations
- Linear stability analysis of Israel-Stewart theory in the case of a nonzero background charge
- Infinite Order Hydrodynamics: An Analytical Example
- Topological modes in relativistic hydrodynamics