Study of Gravastars in Rastall Gravity

Abstract

Gravastars have been considered as a feasible alternative to black holes in the past couple of decades. Stable models of gravastar have been studied in many of the alternative gravity theories besides standard General Relativity (GR). The Rastall theory of gravity is a popular alternative to GR, specially in the cosmological and astrophysical context. Here, we propose a stellar model under the Rastall gravity following Mazur-Mottola's \cite{Mazur2001,Mazur2004} conjecture. The gravastar consists of three regions, viz., ($I$) Interior region, ($II$) Intermediate shell region, and ($III$) Exterior region. The pressure within the interior core region is assumed with a constant negative matter-energy density which provides a repulsive force over the entire thin shell region. The shell is assumed to be made up of fluid of ultrarelativistic plasma which follows the Zel'dovich's conjecture of stiff fluid \cite{Zeldo1962,Zel'dovich1972}. It is also assumed that the pressure is proportional to the matter-energy density according to Zel'dovich's conjecture, which cancel the repulsive force exerted by the interior region. The exterior region is completely vacuum which is described by the Schwarzschild-de Sitter solution. Under all these specifications we obtain a set of exact and singularity-free solutions of the gravastar model presenting several physically valid features within the framework of Rastall gravity. The physical properties of the shell region namely, the energy density, proper length, total energy and entropy are explored. The stability of the gravastar model is investigated using the surface redshift against the shell thickness and maximizing the entropy of the shell within the framework of Rastall gravity.

22 Pages, 6 Figures

References in corpus (66)

• Observational Evidence from Supernovae for an Accelerating Universe and a Cosmological Constant
• Measurements of Omega and Lambda from 42 High-Redshift Supernovae
• Observation of Gravitational Waves from a Binary Black Hole Merger
• Seven-Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Cosmological Interpretation
• The Cosmological Constant and Dark Energy
• First M87 Event Horizon Telescope Results. I. The Shadow of the Supermassive Black Hole
• Modified Gravity and Cosmology
• Cosmological parameters from SDSS and WMAP
• Cosmological Constant - the Weight of the Vacuum
• The Case for a Positive Cosmological Lambda-term
• A Flat Universe from High-Resolution Maps of the Cosmic Microwave Background Radiation
• New Hubble Space Telescope Discoveries of Type Ia Supernovae at z > 1: Narrowing Constraints on the Early Behavior of Dark Energy
• Spectra and Light Curves of Six Type Ia Supernovae at 0.511 < z < 1.12 and the Union2 Compilation
• MAXIMA-1: A Measurement of the Cosmic Microwave Background Anisotropy on angular scales of 10 arcminutes to 5 degrees
• Is the gravitational-wave ringdown a probe of the event horizon?
• Gravitational Vacuum Condensate Stars
• Stable gravastars - an alternative to black holes?
• Maximum bounds on the surface redshift of anisotropic stars
• Bounds on the basic physical parameters for anisotropic compact general relativistic objects
• Gravastars must have anisotropic pressures
• Stable dark energy stars
• How to tell a gravastar from a black hole
• On average properties of inhomogeneous fluids in general relativity II: perfect fluid cosmologies
• The Current Ability to Test Theories of Gravity with Black Hole Shadows
• Compact stars in $f(R,T)$ gravity
• Rastall Cosmology and the ΛCDM Model
• Junctions and thin shells in general relativity using computer algebra I: The Darmois-Israel Formalism
• Gravastars in $f(R,\mathcal{T})$ gravity
• Stable gravastars with generalised exteriors
• Neutron Stars in Rastall Gravity
• Charged gravastars admitting conformal motion
• Gravastar Solutions with Continuous Pressures and Equation of State
• RX J1856-3754: Evidence for a Stiff EOS
• Gravastars supported by nonlinear electrodynamics
• Can accretion disk properties distinguish gravastars from black holes?
• Rotating black hole in Rastall theory
• Did GW150914 produce a rotating gravastar?
• Gravastar Shadows
• Black Hole Solutions in Rastall Theory
• Born-Infeld Phantom Gravastars
• Electrically charged gravastar configurations
• Tidal deformability and I-Love-Q relations for gravastars with polytropic thin shells
• Impact of the Rastall parameter on perfect fluid spheres
• Kerr-Newman-AdS Black Hole Surrounded by Perfect Fluid Matter in Rastall Gravity
• Strange stars in Krori-Barua space-time under f(R; T) gravity
• Charged gravastars in higher dimensions
• The (2+1)-dimensional charged gravastars
• Gravastar energy conditions revisited
• The dark energy equation of state
• The (2+1)-dimensional gravastars
• Relativistic compact stars in $f(T)$ gravity admitting conformal motion
• Noncommutative geometry inspired black holes in Rastall gravity
• Stable and "bounded excursion" gravastars, and black holes in Einstein's theory of gravity
• Gravastars in $f(\mathbb{T},\mathcal{T})$ gravity
• Constraining the Rastall parameters in static spacetimes with galaxy-scale strong gravitational lensing
• Electromagnetic Fields of Slowly Rotating Magnetized Gravastars
• The higher dimensional gravastars
• Study of gravastars under $f(\mathbb{T})$ gravity
• Gravastars with higher dimensional spacetimes
• Energetics in Condensate Star and Wormholes
• Gravastar under the framework of Braneworld Gravity
• Traversable Wormholes Construction in 2+1 Dimensions
• The Einstein dark energy model
• How the Charge Can Affect the Formation of Gravastars
• Radiating Gravastars
• Braneworld Black Holes and Entropy Bounds

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• Stable three-dimensional (un)charged AdS gravastars in gravity's rainbow
• Kuchowicz gravastars in the braneworld formalism
• Stable Gravastar model in Cylindrically Symmetric Space-time
• Thick brane in Rastall gravity
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