Scaling Hydrodynamical Evolution of a Gravitating Dark-fluid Universe

TL;DR

This paper develops a hydrodynamical model for a gravitating dark fluid universe using self-similar solutions, analyzing density and velocity fields and the impact of initial conditions on energy densities.

Contribution

It introduces a new self-similar approach to study the evolution of a gravitating dark fluid with a linear equation of state, including gravitational effects.

Findings

Derived space and time-dependent density and velocity fields.

Analyzed the influence of initial velocity on energy densities.

Explored the role of the equation of state parameter.

Abstract

We present a dark fluid model which contains the general linear equation of state including the gravitation term. The obtained spherical symmetric Euler equation and the continuity equation was investigated with the Sedov-type time-dependent self-similar {\it ansatz} which is capable to describe physically relevant diffusive and dispersive solutions. %The role of the parameter in the equation of state is investigated. As results the space and time dependent fluid density and radial velocity fields are presented and analyzed. Additionally, the role of the initial velocity on the kinetic and total energy densities of the fluid is discussed.