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This manuscript is devoted to analyze hyperbolically symmetric non-static fluid distribution incorporated with heat flux and electromagnetic field. We have developed a general framework in order to examine the dynamic regime of the matter configuration which eventually results in the static spacetime. With the aim of doing this, we constructed the Einstein-Maxwell (EM) field equations and obtained the conservation equation. Furthermore, the formulation of mass function indicates the presence of the negative energy density, which leads towards the significant quantum implications. Taking into account the transport equation, we have observed the thermodynamical attributes of the fluid. Additionally, quasi- homologous constraint has been utilized to construct several models. We have deduced the worthwhile applications of the astrophysical objects by evaluating several analytical solutions in terms of the kinematical variables. [ABSTRACT FROM AUTHOR]

The purpose of this paper is to investigate the non-singular solutions of gravitationally vacuumed condensate star in the realm of the f(R, T, Q) theory, where Q = RσηTση. The three-layered gravastar structure has been constructed in the cylindrical spacetime under the effects of electromagnetism in the modified theory. Furthermore, we have studied the effects of electromagnetism on the effective matter, which involves the perfect fluid and isotropic pressure in it. To gain this objective, we consider the cylindrical spacetime and evaluate the three regions mathematically. The metric coefficients are calculated independently for each region. To match the region I and II at a hypersurface, the junction conditions have been calculated. To figure out the dependency of the thickness of shell on different physical features of gravastar, we interpret it graphically as well as mathematically. Subsequently, the noticeable facts are accomplished. [ABSTRACT FROM AUTHOR]

The present study aims to see how gravitational modification, specifically, the f(T) gravitational field, where T is torsion scalar, impacts static fluid content with hyperbolic symmetry and electromagnetic field. We enlarge Herrera's strategy (Herrera et al. in Phys Rev D 103:024037, 2021) to analyze the impact of electromagnetic field on f(T) gravity. We distinguish the stress–energy tensor by considering the ingredients of the tetrad field in the Minkowski co-ordinate frame, commencing with modified field equations. With the advent of negative density, this sort of fluid is supposed to surpass extreme physical conditions, enabling quantum impacts to be detected. We calculate a viable formulation of mass utilizing the Tolman mass from the viewpoint of f(T) gravity along with the electromagnetic field. The gravitational interference is repulsive, as made evident by the negative value of the Tolman mass. Also, we explored the structure scalars in f(T) gravity and found significant solutions in presence of electric charge. [ABSTRACT FROM AUTHOR]

In this work, the study on static fluid distributions under the influence of electromagnetism has been carried out with an emphasis on the hyperbolically symmetric metric. For this purpose, modified gravitational formulations in the presence of charge are used to calculate the effective energy–momentum tensor, which is then further refined by taking into account tetrad field components in the Minkowski coordinate system. Also, we compute the Tolman mass and a suitable formulation of the mass function. It exhibits that the hyperbolically symmetrical source has a negative effective matter density in all stellar formulations. This demonstrates that the quantum processes together with certain excessive constraints are deemed important to explain any physical implementations under the effects of the electromagnetic field. Additionally, we assessed the structure scalars and implemented the orthogonal splitting of the structure scalars and Riemann tensor in this modified gravity. Subsequently, various explicit precise cosmological solutions and their generating functions are developed. [ABSTRACT FROM AUTHOR]

This paper is dedicated to inspecting the appearance of electromagnetic field, which is caused by the presence of charge in the highly compact object named gravastar in the background of f (R , G) theory. According to conjecture introduced by Mazur and Mottola gravastar must be consisted of three sectors. We have interpreted these sectors by using specific equations of states. Spherically static metric, perfect fluid and the isotropic pressure have been used in order to calculate a singularity free solution. Gravitational mass present in the inner sector of gravastar is changed into electromagnetic mass in the existence of charge. The electromagnetic mass model of inner sector is responsible for stability by providing balance to the repulsive pressure, which is caused by the presence of charge. It is observed that the presence of electrical charge has a significant effect on energy content, entropy and proper length of the shell that is demonstrated with the help of graphs. [ABSTRACT FROM AUTHOR]

The principal idea behind this manuscript is to inspect the complexity of dissipating as well as non-dissipating self-gravitating sources which are coupled with locally anisotropic charged matter. The gravitational equations in the regime of |$f(\mathbb {G})$| (⁠|$\mathbb {G}$| is the Gauss–Bonnet invariant) theory have elaborated for the imperfectly charged stellar configuration to scrutinize the charged object in the presence of |$f(\mathbb {G})$| corrections. The impact of charge distribution on the connection between density inhomogeneity, Weyl tensor, and pressure anisotropy is investigated. By incorporating the constraints of Q H (i.e. the quasi-homologous) evolution and C F = 0, (where C F denotes the complexity factor) multiple analytical solutions to the |$f(\mathbb {G})$| equations of gravity are developed defining the imperfectly charged compact spherical matter. Some of these stellar models (exact solutions) portray a spherical collapsing configuration of a charged fluid in which there arise a cavity about the fluid centre, while other models exhibit a fluid configuration wherein the sphere is totally filled by the fluid. These interior solutions to |$f(\mathbb {G})$| gravitational equations may exhibit some appealing astrophysical phenomenons. [ABSTRACT FROM AUTHOR]

The objective of this article is to investigate the effects of electromagnetic field on the generalization of Lemaître–Tolman–Bondi (LTB) spacetime by keeping in view the Palatini f(R) gravity and dissipative dust fluid. For performing this analysis, we followed the strategy deployed by Herrera et al. (Phys Rev D 82(2):024021, 2010). We have explored the modified field equations along with kinematical quantities and mass function and constructed the evolution equations to study the dynamics of inhomogeneous universe along with Raychauduary and Ellis equations. We have developed the relation for Palatini f(R) scalar functions by splitting the Riemann curvature tensor orthogonally and associated them with metric coefficients using modified field equations. We have formulated these scalar functions for LTB and its generalized version, i.e., GLTB under the influence of charge. The properties of GLTB spacetime are consistent with those of the LTB geometry and the scalar functions found in both cases are comparable in the presence of charge and Palatini f(R) curvature terms. The symmetric properties of generalized LTB spacetime are also studied using streaming out and diffusion approximations. [ABSTRACT FROM AUTHOR]

In this work, we discuss the stability of charged neutron star in the background of f (R ̂) gravity and construct the generalized Tolman–Oppenheimer–Volkoff (TOV) equations. For this, we consider static spherically symmetric geometry to construct the hydrostatic equilibrium equation and deduce TOV equations from modified field equations with electromagnetic effects. We conclude that the generalized TOV equation depicts the stable stars configuration independent of the generic function of the modified gravity if the condition of uniform entropy and chemical composition is assumed. [ABSTRACT FROM AUTHOR]

Assuming a system with spherical symmetry in f(R) gravity filled with dissipative charged and anisotropic matter, we study the impact of density inhomogeneity and local anisotropy on the gravitational collapse in the presence of charge. For this purpose, we evaluated the modified Maxwell field equations, Weyl curvature tensor, and the mass function. Using Misner–Sharp mass formalism, we construct a relation between the Weyl tensor, density inhomogeneity, and local anisotropy. Specifically, we obtain the expression of modified Tolman mass which helps to analyze the influence of charge and dark source terms on different physical factors, also it helps to study the role of these factors on gravitational collapse. [ABSTRACT FROM AUTHOR]

The objective of this paper is to examine the influence of polynomial dark sector cosmic terms on the collapse of electrically charged Lemaître-Tolman-Bondi geometry. We explored a class of solutions for field equations in the existence of electromagnetic field and under the constraint of constant curvature scalar. The influence of model on the dynamics of collapsing object have been discussed by studying its black hole and cosmological horizons. Also, the effects of these dark sources on the time interval between the corresponding singularities and horizons have been studied. We investigated that the process of collapse slows down due to the higher order curvature invariants of polynomial model and electromagnetic field. [ABSTRACT FROM AUTHOR]

One of the striking feature of inhomogeneous matter distribution under the effects of fourth-order gravity and electromagnetic field have been discussed in this manuscript. We have considered a compact spherical celestial star undergoing expansion due to the presence of higher curvature invariants of gravity and imperfect fluid. We have explored the dynamical equations and field equations in gravity. An explicit expression have been found for Weyl tensor and material variables under the dark dynamical effects. Using a viable model, some dynamical variables have been explored from splitting the Riemann curvature tensor. These dark dynamical variables are also studied for charged dust cloud with and without the constraint of constant Ricci scalar. [ABSTRACT FROM AUTHOR]

We study the influence of Palatini $f(R)$ gravity and tilted observer on the dynamics of Lemaître-Tolman-Bondi space-time in the presence of electromagnetic field. The imperfect charged fluid seen by tilted observer is considered in comparison with charged dust fluid seen by nontilted observer. We develop the relations between tilted and nontilted variables by including electric charge in Palatini $f(R)$ gravity. In this framework, we explore the evolution of energy density inhomogeneities for tilted and nontilted observers by calculating the energy conservation laws for charged fluid. Finally, we evaluate a constraint on the electric charge in the collapse of stellar objects, which leads to the instability of nontilted congruence. [ABSTRACT FROM AUTHOR]

In this paper, we have investigated the role of different fluid parameters particularly electromagnetic field and f(R) corrections on the evolution of cylindrical compact object. We have explored the modified field equations, kinematical quantities and dynamical equations. An expression for the mass function has been found in comparison with the Misner-Sharp formalism in modified gravity, after which different mass-radius diagrams are drawn. The coupled dynamical transport equation have been formulated to discuss the role of thermoinertial effects on the inertial mass density of the cylindrical relativistic interior. Finally, we have presented a framework, according to which all possible solutions of the metric f(R)-Maxwell field equations coupled with static fluid can be written through set of scalar functions. It is found that modified gravity induced by Lagrangians f(R) = αR2, f(R) = αR2 - βR and f (R) = αR2-βR 1+γR are likely to host more massive cylindrical compact objects with smaller radii as compared to general relativity. [ABSTRACT FROM AUTHOR]

We study evolutionary properties of isotropic charged spherical Lemaître-Tolman-Bondi fluid undergoing non-adiabatic collapse with general f( R) background. We explore exact analytical models of Maxwell- f( R) field equations with constant Ricci scalar. The dynamics of the collapsing system is investigated through system energy content, cosmological and black hole horizons in the presence of electromagnetic field. It is concluded that in addition to matter variables and f( R) corrections, the charge also affects the time interval between formation of respective horizons and singularities. We also find that f( R) corrections as well as electromagnetic field tend to slow down the collapsing process. [ABSTRACT FROM AUTHOR]

In this paper, we analyze the role of electromagnetic field and generalized Carrol-Duvvuri-Trodden-Turner (CDTT) model on the existence of homogeneous energy density. For this purpose, we model spherical star with anisotropic matter distribution dissipating in the mode of heat and radiation density. To develop a relationship between the Weyl tensor and matter parameters, we construct two evolution equations. We explore inhomogeneity parameters for particular cases of non-dissipative and dissipative matter distributions. It is concluded that in addition to other fluid variables higher order f( R) corrections, relaxation processes and electromagnetic field affect the energy density inhomogeneity of spherical stars. [ABSTRACT FROM AUTHOR]

We explore the factors of inhomogeneity in the spherically symmetric distribution of collapsing fluid under the effect of electromagnetic field in f (G) theory. Modified Bianchi identities and two significant equations for the Weyl tensor are formulated to get help in the analysis. Causes of inhomogeneity are analyzed by considering the non-radiating and radiating charged fluid. The non-dissipative type of fluid contains pressureless, isotropic and anisotropic fluid. It is observed that for anisotropic fluid, the inhomogeneity corresponds to the structure scalar. For dissipative dust, the effects of relaxation time in terms of electromagnetic field are brought out. • We explore the factors of inhomogeneity in the spherically symmetric matter distribution under Maxwell-f(G) theory. • Modified Bianchi identities and evolution equations for the Weyl tensor are formulated for the required results. • Causes of inhomogeneity are analyzed by considering the non-radiating and radiating charged fluid. [ABSTRACT FROM AUTHOR]

Abstract: This work investigates the dynamical instability of the relativistic self-gravitating collapsing fluids with electromagnetic field in Carrol–Duvvuri–Trodden–Turner (CDTT) model for spherical symmetric spacetime. In this scenario, we provide dynamical equations from the contracted Bianchi identities for the usual, effective dark source and electromagnetic energy–momentum tensor. The perturbation technique is used on the metric variables which ultimately induce perturbation on the selected model and on the physical variables. We conclude that higher curvature terms of CDTT model, density profile, electromagnetism and pressure anisotropy affect the range of instability at the Newtonian and post Newtonian regimes. It is worthwhile to mention here that our results approach asymptotically to general relativity solutions when . [Copyright &y& Elsevier]

The aim of this paper is to analyse the role of electromagnetic field and a viable Carroll–Duvvuri–Trodden–Turner (CDTT) model, $f(R)=R+\rho \frac{{\delta }^4}{R}$, in the range of dynamical instability. We assume non-viscous charged collapsing cylindrical star with heat flux dissipation. We formulate dynamical equations through perturbation scheme on the metric variables which eventually cause perturbation on physical variables as well as chosen f (R) model. The evolution of the matter variables is discussed with the help of these equations. It is concluded that the range of dynamical instability depends upon the electric field intensity, density profile, pressure and the curvature terms of the CDTT model. We find that our results of Newtonian and post-Newtonian regimes reduce asymptotically to General Relativity solutions as δ → 0. [ABSTRACT FROM AUTHOR]

• A new solution of charged gravastars with isotropic matter configuration in the framework of f (R, T) theory of gravity has been presented. • We present an exact solution that free from event horizon and non-singular for this our new model. • We have found some physical aspects like length, energy, entropy and equation of state for charged spherical gravastar distribution. We have studied a new solution of charged gravastars with isotropic matter configuration in the framework of f (R, T) theory of gravity. For this purpose, we have assumed the electric charge as a constant. This stellar structure divided into three different regions: The preliminary part shows the interior charged region in which pressure equals to the negative density, second is the intermediate charged shell which is assumed to be very thin and filled with ultrarelativistic stiff fluid and the last corresponds to the electrovacuum region which is defined by an exterior Reissner-Nordström solution. Under these assumptions, we have found some physical aspects like length, energy, entropy and equation of state for charged spherical gravastar distribution. Moreover, we present an exact solution that free from event horizon and non-singular for this our new model. [ABSTRACT FROM AUTHOR]

In this manuscript, we study the construction of static cylindrically symmetric thin shell wormhole models with an electric charge in the background of f (R , T) gravity. We utilized "cut and paste" technique to match two identical spacetimes across the separation hypersurface Σ. In this gravity, f is a generic function of the Ricci scalar (R) and the trace of the stress-energy tensor (T), as the gravitational sources. We continue our systematic investigation by using specific f (R , T) model with quadratic corrections in R. In this scenario, we assume that the isotropic perfect fluid adequately represents the matter sector, implying that matter at the shell is sustained by generalized Chaplygin gas. Using generalized Chaplygin gas, to ensure a consistent matching of the two spacetimes across the separation hypersurface Σ, suitable boundary conditions and constraints are imposed. These conditions guarantee the continuity of the metric coefficients, the electric charge distribution, and other relevant quantities at the thin shell within the framework of the quadratic f (R , T) gravity. The effects of mass, equation of state parameters, and electric charge are examined on the stability of static wormhole models for the widest possible range of model parameters. The positive value of the second derivative of potential at throat radius is used to characterize the stability requirement which is indicated via plots. We study the presence of charge which might affect the stability region of constructed wormhole. It is suggested that a charged wormhole model might be more stable than an uncharged one. [ABSTRACT FROM AUTHOR]