Accretion onto a Quintessence Contaminated Rotating Black Hole : Violating the Lower Limit for Eta over s

TL;DR

This paper models viscous accretion onto a rotating black hole influenced by quintessence dark energy using a pseudo-Newtonian potential, analyzing flow dynamics and viscosity limits.

Contribution

It introduces a new pseudo-Newtonian potential for quintessence-contaminated black holes and studies accretion flow properties without complex relativistic equations.

Findings

Flow profiles vary with black hole spin and quintessence parameters.

Density distributions align with observational data.

Shear viscosity to entropy density ratio is compared to theoretical limits.

Abstract

Viscous accretion flow around a rotating supermassive black hole sitting in a quintessence tub is studied in this article. To introduce such a dark energy contaminated black hole's gravitational force, a new pseudo-Newtonian potential is used. This pseudo-Newtonian force can be calculated if we know the distance from the black hole's center, spin of the black hole and equation of state of the quintessence inside which the black hole is considered to lie. This force helps us to avoid complicated nonlinearity of general relativistic field equations. Transonic, viscous, continuous and Keplerian flow is assumed to take place. Fluid speed, sonic speed profile and specific angular momentum to Keplerian angular momentum ratio are found out for different values of spin parameter and quintessence parameter. Density variation is built and tallied with observations. Shear viscosity to entropy density ratio is constructed for our model and a comparison with theoretical lower limit is done.