Article
Physics, Multidisciplinary
Shiraz Khan, S. A. Mardan, M. A. Rehman
Summary: This manuscript investigates the generalized polytropes in the presence of charge using complexity factor. Two sets of differential equations are solved under different values of charge and parameters, and the solutions are discussed graphically.
EUROPEAN PHYSICAL JOURNAL PLUS
(2021)
Article
Physics, Particles & Fields
M. Azam, Waseem Sajjad, S. A. Mardan
Summary: This paper discusses the theory of relativistic charged double polytropes with a generalized polytropic equation of state. A general framework is presented to develop the Lane-Embden equations for spherically symmetric charged configurations. The stability of these developed polytropes is investigated using the Tolman mass, and the structure of these polytropes under various constraints is examined.
EUROPEAN PHYSICAL JOURNAL C
(2022)
Article
Physics, Particles & Fields
S. A. Mardan, I Noureen, A. Khalid
Summary: The study successfully constructed a relativistic core-envelope model, matching core, envelope, and the Reissner Nordstrom exterior regions, discussing various physical parameters in compact stars while maintaining non-singularity and continuity. The impact of a charged compact object together with the core-envelope model on mass, radius, and compactification factor was described through graphical representation in both core and envelope regions. The stability of the model was analyzed using Tolman-Oppenheimer-Volkoff equations and radial sound speed.
EUROPEAN PHYSICAL JOURNAL C
(2021)
Article
Physics, Particles & Fields
Shiraz Khan, S. A. Mardan, M. A. Rehman
Summary: In this paper, the authors incorporate the useful aspects of astrophysics, namely generalized polytropes, Karmarkar condition, and complexity factor, to study compact objects. A charged anisotropic fluid distribution is used under static spherical symmetry. The authors develop a framework for class I generalized charged Lane-Emden equations and solve them numerically. Finally, the solutions are discussed graphically.
EUROPEAN PHYSICAL JOURNAL C
(2022)
Article
Astronomy & Astrophysics
S. D. Maharaj, D. Kileba Matondo
Summary: New classes of exact solutions to the Einstein field equations are found, where the matter distribution satisfies a generalized polytropic equation of state and is uncharged with anisotropic pressures. Equations of state for polytropes and quark matter are contained as special cases. The matter variables and metric potentials can be obtained explicitly. Known solutions arise as special cases for a particular choice of the gravitational potential made in this analysis. A detailed physical analysis indicates that the model is well behaved.
Article
Physics, Particles & Fields
Shiraz Khan, S. A. Mardan, M. A. Rehman
Summary: In this paper, complexity factor was used with a generalized polytropic equation of state to develop two consistent systems of three differential equations, providing a general framework for modified Lane-Emden equations. Anisotropic fluid distribution in cylindrical static symmetry was considered under two cases of generalized polytropic equation of state (i) mass density μ(0) and (ii) energy density μ. A graphical analysis was conducted to obtain numerical solutions for these systems of three differential equations.
EUROPEAN PHYSICAL JOURNAL C
(2021)
Article
Astronomy & Astrophysics
P. Leon, E. Fuenmayor, E. Contreras
Summary: We discussed the effects of small fluctuations in local anisotropy and energy density on cracking in spherical compact objects with a polytropic equation of state. Departures from equilibrium were shown to lead to cracking across a wide range of parameter values. Potential applications of the results to astrophysical scenarios were also highlighted.
Article
Physics, Particles & Fields
S. K. Maurya, Asma Mohammed Al Aamri, Athari Khalifa Al Aamri, Riju Nag
Summary: A new systematic approach to finding exact gravitationally decoupled anisotropic spherical solutions in the presence of electric charge is presented using the complete geometric deformation methodology. The study applies well-known mimic approaches and equation of state to determine deformation functions and discusses the physical properties and stability of the solution. Predictions for radii, mass-radius ratio, and thermodynamic observables for compact objects under different decoupling parameters are also provided.
EUROPEAN PHYSICAL JOURNAL C
(2021)
Article
Physics, Multidisciplinary
Grigoris Panotopoulos, Anirudh Pradhan, Takol Tangphati, Ayan Banerjee
Summary: This article investigates the possibility of compact charged spheres made of a charged perfect fluid in the context of the 4D Einstein-Gauss-Bonnet (EGB) gravity theory. By rescaling the Gauss-Bonnet (GB) coupling constant and redefining gravity in 4D, the GB term contributes to the gravitational dynamics. The analysis is based on a polytropic equation of state and a proportional relation between charge density and energy density. The article derives hydrostatic equilibrium equations and solves them numerically to obtain mass-radius relations for charged compact stars. It also explores the relationship between mass and central mass density, as well as the relation between electric charge and maximum mass of compact stars in this gravity theory. The article concludes that charged stars may exist in nature and their deviation from traditional models may be observable in future astrophysical probes.
CHINESE JOURNAL OF PHYSICS
(2022)
Article
Astronomy & Astrophysics
Shiraz Khan, S. A. Mardan, M. A. Rehman
Summary: The main theme of this work is the development of complexity-induced generalized frameworks for static cylindrical polytropes. Two different definitions of generalized polytopes with charged anisotropic inner fluid distribution are considered. A new methodology, based on the complexity factor, is presented for generating consistent sets of differential equations. The work concludes with a graphical analysis of the developed frameworks.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2022)
Article
Multidisciplinary Sciences
Mohamed S. Aboueisha, Mohamed I. Nouh, Eamad A. -B. Abdel-Salam, Tarek M. Kamel, M. M. Beheary, Kamel A. K. Gadallah
Summary: This article explores the effects of relativistic effects on polytropic gas spheres, formulating fractional TOV equations and introducing an analytical solution. The use of power series expansions and techniques such as the Euler-Abel transformation and Pade approximation improves the convergence of the obtained solutions. The study calculates the volume and mass changes for different values of the relativistic and fractional parameters and determines the maximum mass and minimum radius of white dwarfs modeled with different parameters.
SCIENTIFIC REPORTS
(2023)
Article
Physics, Particles & Fields
Daniel Suarez-Urango, Justo Ospino, Hector Hernandez, Luis A. Nunez
Summary: This paper explored the physical acceptability conditions for anisotropic matter configurations in General Relativity and found that polytropes based on the total energy density are more viable than those with baryonic density, and small positive local anisotropies produce acceptable models.
EUROPEAN PHYSICAL JOURNAL C
(2022)
Article
Astronomy & Astrophysics
Ben Kain
Summary: This study explores the stability of fermion-charged-boson stars by computing critical curves across parameter space, analyzing the contributions of fermion and boson sectors to the total mass of the star, and presenting mass-radius diagrams demonstrating that an increase in charge can lead to more massive and compact stars.
Article
Astronomy & Astrophysics
Vasileios Karageorgopoulos, Konstantinos N. Gourgouliatos, Vassilis Geroyannis
Summary: The study explores solutions of spherical winds driven by pressure within a gravitational field. By applying the Complex Plane Strategy, numerical solutions of polytropic winds are obtained, which demonstrate physical behavior at various points. The research further examines the impact of polytropic index, mass-loss rate, and temperature on the velocity profile and transition points of the wind flow.
ASTRONOMY AND COMPUTING
(2021)
Article
Physics, Particles & Fields
S. K. Maurya, M. Govender, Ksh Newton Singh, Riju Nag
Summary: In this study, we investigate the characteristics of an anisotropic stellar object using the polytropic solution within the framework of Einstein-Gauss-Bonnet (EGB) gravity. Anisotropy is introduced through the minimally gravitational decoupling method. The analysis of the exact solution for the gravitational potentials reveals novel features of the compact object. The EGB coupling constant and the decoupling parameter are found to play important roles in modifying the effective density and radial profiles at each interior point of the object, as well as inducing a change in the trends of the effective tangential pressure.
EUROPEAN PHYSICAL JOURNAL C
(2022)
Article
Physics, Particles & Fields
M. Azam, S. A. Mardan, I. Noureen, M. A. Rehman
EUROPEAN PHYSICAL JOURNAL C
(2016)
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Physics, Particles & Fields
S. A. Mardan, M. Azam
EUROPEAN PHYSICAL JOURNAL C
(2017)
Article
Physics, Particles & Fields
S. A. Mardan, I Noureen, M. Azam, M. A. Rehman, M. Hussan
EUROPEAN PHYSICAL JOURNAL C
(2018)
Article
Physics, Particles & Fields
I. Noureen, S. A. Mardan, M. Azam, W. Shahzad, S. Khalid
EUROPEAN PHYSICAL JOURNAL C
(2019)
Article
Physics, Multidisciplinary
S. A. Mardan, A. Asif, I. Noureen
EUROPEAN PHYSICAL JOURNAL PLUS
(2019)
Article
Physics, Particles & Fields
Shiraz Khan, S. A. Mardan, M. A. Rehman
EUROPEAN PHYSICAL JOURNAL C
(2019)
Article
Physics, Particles & Fields
S. A. Mardan, M. Rehman, I. Noureen, R. N. Jamil
EUROPEAN PHYSICAL JOURNAL C
(2020)
Article
Physics, Multidisciplinary
S. A. Mardan, A. A. Siddiqui, I. Noureen, R. N. Jamil
EUROPEAN PHYSICAL JOURNAL PLUS
(2020)
Article
Astronomy & Astrophysics
I. Noureen, Usman-ul-Haq, S. A. Mardan
Summary: This work discusses the evolution of spherically symmetric charged anisotropic viscous fluids in the framework of f(R,T) gravity, analyzing the impact on the stability of stars. The study constructs modified Einstein Maxwell field equations and applies a perturbation scheme for stability analysis. The research observes significant influences of charge, fluid distribution, electromagnetic field, viscosity, and mass on the collapsing process and stability of celestial objects.
INTERNATIONAL JOURNAL OF MODERN PHYSICS D
(2021)
Article
Physics, Multidisciplinary
Shiraz Khan, S. A. Mardan, M. A. Rehman
Summary: This manuscript investigates the generalized polytropes in the presence of charge using complexity factor. Two sets of differential equations are solved under different values of charge and parameters, and the solutions are discussed graphically.
EUROPEAN PHYSICAL JOURNAL PLUS
(2021)
Article
Physics, Particles & Fields
Shiraz Khan, S. A. Mardan, M. A. Rehman
Summary: In this paper, complexity factor was used with a generalized polytropic equation of state to develop two consistent systems of three differential equations, providing a general framework for modified Lane-Emden equations. Anisotropic fluid distribution in cylindrical static symmetry was considered under two cases of generalized polytropic equation of state (i) mass density μ(0) and (ii) energy density μ. A graphical analysis was conducted to obtain numerical solutions for these systems of three differential equations.
EUROPEAN PHYSICAL JOURNAL C
(2021)
Article
Physics, Particles & Fields
S. A. Mardan, I Noureen, A. Khalid
Summary: The study successfully constructed a relativistic core-envelope model, matching core, envelope, and the Reissner Nordstrom exterior regions, discussing various physical parameters in compact stars while maintaining non-singularity and continuity. The impact of a charged compact object together with the core-envelope model on mass, radius, and compactification factor was described through graphical representation in both core and envelope regions. The stability of the model was analyzed using Tolman-Oppenheimer-Volkoff equations and radial sound speed.
EUROPEAN PHYSICAL JOURNAL C
(2021)
Article
Physics, Particles & Fields
M. Azam, Waseem Sajjad, S. A. Mardan
Summary: This paper discusses the theory of relativistic charged double polytropes with a generalized polytropic equation of state. A general framework is presented to develop the Lane-Embden equations for spherically symmetric charged configurations. The stability of these developed polytropes is investigated using the Tolman mass, and the structure of these polytropes under various constraints is examined.
EUROPEAN PHYSICAL JOURNAL C
(2022)
Article
Astronomy & Astrophysics
M. Azam, S. A. Mardan
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2017)
