Stability of d-dimensional gravastars with variable equation of state

This paper deals with general thermodynamics for the universe filled with a perfect fluid, obeying an equation of state p = ω(z)ρ where the varying equation of the state parameter is chosen as two-index parametrization models namely: (a) linear redshift parametrization: ω(z) = ω0 + ω1z or (b) Jassal–Bagla–Padmanabhan (JBP) parametrization: [Formula: see text] where ω0, ω1 are constants. The behavior of temperature and the thermodynamic stability have been discussed. The thermal equation of state depends on both temperature and volume. As the universe evolves the fluid cools down obeying third law of thermodynamics and there will be thermodynamic stability during the expansion process without any phase transition or passing through any critical point.

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Variable Equation of State for Generalized Dark Energy Model

International Journal of Theoretical Physics ◽

10.1007/s10773-011-0766-2 ◽

2011 ◽

Vol 50 (9) ◽

pp. 2687-2696 ◽

Cited By ~ 25

Author(s):

Saibal Ray ◽

Farook Rahaman ◽

Utpal Mukhopadhyay ◽

Ruby Sarkar

Keyword(s):

Dark Energy ◽

Equation Of State ◽

Dark Energy Model ◽

Energy Model ◽

Variable Equation

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Asymptotically flat wormhole solutions with variable equation-of-state parameter

Physical Review D ◽

10.1103/physrevd.99.104037 ◽

2019 ◽

Vol 99 (10) ◽

Author(s):

F. Parsaei ◽

S. Rastgoo

Keyword(s):

Equation Of State ◽

State Parameter ◽

Asymptotically Flat ◽

Equation Of State Parameter ◽

Variable Equation

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Stability of a charged rotating BTZ thin shell with a different variable equation of state

Modern Physics Letters A ◽

10.1142/s0217732321500863 ◽

2021 ◽

pp. 2150086

Author(s):

A. Eid

Keyword(s):

Black Holes ◽

Equation Of State ◽

Thin Shell ◽

Mechanical Stability ◽

Chaplygin Gas ◽

Throat Radius ◽

Generalized Chaplygin Gas ◽

Radial Perturbation ◽

Btz Black Holes ◽

Variable Equation

Dynamics of charged rotating BTZ black holes in 2 + 1 dimensions by using the cut and paste approach is discussed. Due to the mechanical stability of rotating charged BTZ thin shell, the radial perturbation about the equilibrium throat radius and three variable equation of state (EoS) is analyzed. Several examples are displayed satisfying it, such as variable Phantom-like, variable Chaplygin gas and variable modified generalized Chaplygin gas.

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DARK ENERGY MODELS WITH VARIABLE EQUATION OF STATE PARAMETER

International Journal of Modern Physics D ◽

10.1142/s0218271810016488 ◽

2010 ◽

Vol 19 (04) ◽

pp. 475-487 ◽

Cited By ~ 9

Author(s):

UTPAL MUKHOPADHYAY ◽

SAIBAL RAY ◽

FAROOK RAHAMAN

Keyword(s):

Dark Energy ◽

Equation Of State ◽

Deceleration Parameter ◽

State Parameter ◽

Five Dimensions ◽

Energy Models ◽

Variable Λ ◽

Equation Of State Parameter ◽

Variable Equation

Two phenomenological variable Λ models, viz.Λ ~ (ȧ/a)2 and Λ ~ ρ, have been studied under the assumption that the equation of state parameter ω is a function of time. The selected Λ models are found to be equivalent both in four and five dimensions. The possibility of signature flip of the deceleration parameter is also shown.

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Stability of spherically symmetric timelike thin-shells in general relativity with a variable equation-of-state

International Journal of Modern Physics D ◽

10.1142/s0218271817501589 ◽

2017 ◽

Vol 26 (14) ◽

pp. 1750158 ◽

Cited By ~ 3

Author(s):

S. Habib Mazharimousavi ◽

M. Halilsoy ◽

S. N. Hamad Amen

Keyword(s):

General Relativity ◽

Equation Of State ◽

Energy Density ◽

Surface Energy ◽

Thin Shell ◽

Minkowski Spacetime ◽

Thin Shells ◽

Spherically Symmetric ◽

Surface Energy Density ◽

Variable Equation

We study spherically symmetric timelike thin-shells in [Formula: see text]-dimensional bulk spacetime with a variable equation-of-state for the fluid presented on the shell. In such a fluid, the angular pressure [Formula: see text] is a function of both surface energy density [Formula: see text] and the radius [Formula: see text] of the thin-shell. Explicit cases of the thin shells connecting two nonidentical cloud of strings spacetimes and a flat Minkowski spacetime to the Schwarzschild metric are investigated.

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