Speaker
Description
Hydrokinetic formalism is a deterministic set of relaxation type equations that tracks the evolution of n-point correlation functions of stochastic hydrodynamic quantities. Hydrokinetic formalism is a complementary approach to solving the Stochastic Differential Equations (SDE) for fluctuating hydrodynamics. Hydrokinetics is comparatively easier to solve than the SDEs, which need to deal with arbitrarily large gradients. This talk systematically compares the two approaches for the propagation and diffusion of conserved charge fluctuations in the 1D Bjorken hydrodynamic model. We solve the causal Catteneo noise in the SDE approach [1] and quantify the causality constraints on the evolution of the two-point correlation of charge fluctuations. Results are compared with those from Hydrokinetics in the white-noise limit as a function of wavelength. We further explore the consequence of colored noises on the two-point correlation of charge fluctuations. By subtracting the self-correlation term, we obtain a characteristic power-law decay of the two-point correlator as a function of the time, which agrees with the hydrokinetic approach.
[1] A. De, C. Plumberg and J. I. Kapusta, "Calculating Fluctuations and Self-Correlations Numerically for Causal Charge Diffusion in Relativistic Heavy-Ion Collisions'', Phys. Rev. C102, 024905 (2020)
