Symmetry constraints on generalizations of Bjorken flow

TL;DR

This paper presents an exact solution to relativistic viscous hydrodynamics describing a finite-sized medium expanding radially and longitudinally, based on symmetry constraints within the conformal group.

Contribution

It introduces a novel generalization of Bjorken flow incorporating finite transverse size and radial expansion, derived from symmetry considerations.

Findings

Exact solution of relativistic Navier-Stokes equations for the generalized flow

Flow characterized by conformal symmetry constraints

Applicable to finite-sized, expanding quark-gluon plasma models

Abstract

I explain a generalization of Bjorken flow where the medium has finite transverse size and expands both radially and along the beam axis. If one assumes that the equations of viscous hydrodynamics can be used, with p=epsilon/3 and zero bulk viscosity, then the flow I describe can be developed into an exact solution of the relativistic Navier-Stokes equations. The local four-velocity in the flow is entirely determined by the assumption of symmetry under a subgroup of the conformal group.