Threshold drop in accretion density if dark energy is accreting onto a supermassive black hole

Abstract

Recent studies of galactic cores tell us that supermassive black holes are hosted at each of these cores. We got some evidences even. Besides, dark energy is expected to be distributed all over in our universe. Dark matter halo, on the other hand, could be found around the galactic regions. Though the natures of spans of them are not clearly measured. Galactic structures are supposed to be formed out of dark matter clustering. Some examples of supermassive black holes in the central regions of high redshift galaxies say that the concerned supermassive black holes have completed their constructions in a time less than it generally should be. To justify such discrepancies, we are forced to model about existences of black hole mimickers and exotic phenomena acting near the supermassive black holes. Motivated by these we study the natures of exotic matters, especially dark energy near the black holes. We choose modified Chaplygin gas as dark energy candidate. Again, the descriptions of gravitational waves or the attenuations of them when they are tunnelling through cosmological distances help us to measure the shear viscosity of the medium through which the waves have been travelled. Delayed decaying models of dark matters also suggest that dark energy and viscosity may come up as a byproduct of such decays or interactions. We consider the viscous nature of the medium, i.e., the dark energy. To do so, we choose an alpha-disc model as proposed by Shakura and Sunyaev. We study the variations of densities through accretion and wind branches for a different amount of viscosity regulated by the Shakura-Sunyaev's alpha parameter, spin parameter and different properties of accreting fluids, viz, the properties of adiabatic fluid and modified Chaplygin gas. We compare these results with each other and some existing density profiles drawn from observational data-based simulations. We follow that our result supports the data observed till date. Specifically, we see the wind to get stronger for dark energy as accreting agent. Besides, we see the accretion to have a threshold drop if the viscosity is chosen along with the repulsive effects of dark energy.

Viscous dark energy accretion activities : sonic speed, angular momentum and Mach number studies

“…We have seen in the works [34][35][36] that the accretion disc is truncated as Chaplygin gas is accreted. The cause is better understood if we study the λ λ k curves.…”

“…To locate the density jumps across the shock, we take the help of the article [36]. At each radius, the value of ∂ φ ρ(x , φ) can be calculated to identify the region where the value exceeds one.…”

“…Physically, this interprets that matter is being thrown out with extreme speed and nothing is allowed to fall in. Viscosity is added to this model and studied in [34][35][36] and [37] to establish that viscosity will catalyze the whole process of accretion and as a result, the density of the accreting fluid drops drastically as we proceed towards the central black hole. Other physical quantities like Mach number, spin speed etc were not studied till date.…”

Accretion onto a quintessence contaminated rotating black hole: violating the lower limit for eta over s

“…On the contrary, the wind branch turns to be parallel to u axis while modified Chaplygin gas is accreting (Refs. [85,86]). These two extremely inclinedness are not smoothly changed at all.…”

Yukawa black holes from interacting vacuum

“…The issue of dark energy in black hole physics has been a subject of interest over the last years [1][2][3][4][5][6][7]. In [3], for instance, the authors examine Kerr-Newman-AdS solutions of the Einstein-Maxwell equations considering a quintessence field around a black hole with multiple horizons.…”