Regular black hole motion and stellar orbital resonances

In this paper, we attempt to further study the heat engine efficiency for the regular black hole (BH) with an anti-de Sitter (AdS) background where the working material is the Hayward–AdS (HAdS) BH. In the extended phase space, we investigate the heat engine efficiency of the HAdS BH by defining the cosmological constant as the thermodynamic pressure P and deriving the mechanical work from the PdV terms. Then, we obtain the relation between the efficiency and the entropy/pressure and plot these function figures. Meanwhile, we compare the relation between the HAdS BH with that of the Bardeen–AdS (BAdS) BH, where it is found that the efficiency of the HAdS BH increases with increase in the magnetic charge q in contrast to that of the BAdS BH decrease with increase in the magnetic charge q. We found that the HAdS BH is more efficient than the BAdS BH, and guess that it is related to the BH structure.

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Mimicking Black Holes in General Relativity

10.26686/wgtn.14361101.v1 ◽

2021 ◽

Author(s):

Thomas Berry

Keyword(s):

Black Holes ◽

General Relativity ◽

Black Hole ◽

Thin Shell ◽

Classical General Relativity ◽

Regular Black Hole ◽

Regular Black Holes ◽

Traversable Wormholes ◽

Hole Model ◽

Linearised Stability

The central theme of this thesis is the study and analysis of black hole mimickers. The concept of a black hole mimicker is introduced, and various mimicker spacetime models are examined within the framework of classical general relativity. The mimickers examined fall into the classes of regular black holes and traversable wormholes under spherical symmetry. The regular black holes examined can be further categorised as static spacetimes, however the traversable wormhole is allowed to have a dynamic (non-static) throat. Astrophysical observables are calculated for a recently proposed regular black hole model containing an exponential suppression of the Misner-Sharp quasi-local mass. This same regular black hole model is then used to construct a wormhole via the "cut-and-paste" technique. The resulting wormhole is then analysed within the Darmois-Israel thin-shell formalism, and a linearised stability analysis of the (dynamic) wormhole throat is undertaken. Yet another regular black hole model spacetime is proposed, extending a previous work which attempted to construct a regular black hole through a quantum "deformation" of the Schwarzschild spacetime. The resulting spacetime is again analysed within the framework of classical general relativity. In addition to the study of black hole mimickers, I start with a brief overview of the theory of special relativity where a new and novel result is presented for the combination of relativistic velocities in general directions using quaternions. This is succeed by an introduction to concepts in differential geometry needed for the successive introduction to the theory of general relativity. A thorough discussion of the concept of spacetime singularities is then provided, before analysing the specific black hole mimickers discussed above.

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Simple regular black hole with logarithmic entropy correction

The European Physical Journal C ◽

10.1140/epjc/s10052-016-4417-x ◽

2016 ◽

Vol 76 (10) ◽

Cited By ~ 7

Author(s):

Nicolás Morales-Durán ◽

Andrés F. Vargas ◽

Paulina Hoyos-Restrepo ◽

Pedro Bargueño

Keyword(s):

Black Hole ◽

Regular Black Hole ◽

Entropy Correction

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Gravitational analysis of neutral regular black hole in Rastall gravity

Modern Physics Letters A ◽

10.1142/s0217732320502259 ◽

2020 ◽

Vol 35 (27) ◽

pp. 2050225 ◽

Cited By ~ 1

Author(s):

Riasat Ali ◽

Muhammad Asgher ◽

M. F. Malik

Keyword(s):

Black Hole ◽

Wave Equation ◽

Quantum Gravity ◽

Generalized Uncertainty Principle ◽

Gravity Effect ◽

Tunneling Radiation ◽

Regular Black Hole ◽

Quantum Gravity Effect ◽

Stability And Instability ◽

The Stability

This paper is devoted to the tunneling radiation and quantum gravity effect on tunneling radiation of neutral regular black hole in Rastall gravity. We analyzed the tunneling radiation and Hawking temperature of neutral regular black hole by applying the Hamilton-Jacobi ansatz phenomenon. Lagrangian wave equation have been investigated by generalized uncertainty principle (GUP), using the WKB-approximation and calculated the tunneling rate as well as temperature. Furthermore, we analyzed the temperature of this neutral regular black hole in the presence of gravity. The stability and instability of neutral regular black hole are also analyzed.

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Entropy bound of horizons of some regular black holes

Modern Physics Letters A ◽

10.1142/s0217732320500704 ◽

2020 ◽

Vol 35 (10) ◽

pp. 2050070

Author(s):

Ujjal Debnath

Keyword(s):

Black Holes ◽

Heat Capacity ◽

Black Hole ◽

Specific Heat ◽

Surface Area ◽

Event Horizon ◽

Specific Heat Capacity ◽

Thermodynamic Quantities ◽

Event Horizons ◽

Regular Black Hole

We study the four-dimensional (i) modified Bardeen black hole, (ii) modified Hayward black hole, (iii) charged regular black hole and (iv) magnetically charged regular black hole. For modified Bardeen black hole and modified Hayward black hole, we found only one horizon (event horizon) and then we found some thermodynamic quantities like the entropy, surface area, irreducible mass, temperature, Komar energy and specific heat capacity on the event horizon. We here study the bounds of the above thermodynamic quantities for these black holes on the event horizon. Then, we examine the thermodynamics stability of the black holes with some conditions. Next, we studied the charged regular black hole and magnetically charged regular black hole and found two horizons (Cauchy and event horizons) of these black holes. Then, we found the entropy, surface area, irreducible mass, temperature, Komar energy and specific heat capacity on the Cauchy and event horizons. Then, we get some conditions for thermodynamic stability/instability of the black holes. We found the radius of the extremal horizon and Christodoulou–Ruffiini mass and then analyze the above thermodynamic quantities on the extremal horizon. We calculate the sum/subtraction, product, division and sum/subtraction of inverse of surface areas, entropies, irreducible masses, temperatures, Komar energies and specific heat capacities on both the horizons. From these, we found the bounds of the above quantities on the horizons.

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Greybody factor and quasinormal modes of Regular Black Holes

The European Physical Journal C ◽

10.1140/epjc/s10052-020-08445-2 ◽

2020 ◽

Vol 80 (10) ◽

Author(s):

Ángel Rincón ◽

Victor Santos

Keyword(s):

Black Holes ◽

Black Hole ◽

Angular Momentum ◽

Classical Solution ◽

Quantum Number ◽

Quasinormal Modes ◽

Wkb Method ◽

Regular Black Hole ◽

Gravitational Perturbations ◽

Black Hole Solutions

AbstractIn this work, we investigate the quasinormal frequencies of a class of regular black hole solutions which generalize Bardeen and Hayward spacetimes. In particular, we analyze scalar, vector and gravitational perturbations of the black hole with the semianalytic WKB method. We analyze in detail the behaviour of the spectrum depending on the parameter p/q of the black hole, the quantum number of angular momentum and the s number. In addition, we compare our results with the classical solution valid for $$p = q = 1$$ p = q = 1 .

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