The Finslerian Wormhole model with f(R,T)f(R, T)f(R,T) gravity (original) (raw)

The Finslerian wormhole models

2016

We present models of wormhole under the Finslerian structure of spacetime. This is a sequel of our previous work (Eur Phys J 75:564, 2015) where we constructed a toy model for compact stars based on the Finslerian spacetime geometry. In the present investigation, a wide variety of solutions are obtained that explore wormhole geometry by considering different choices for the form function and energy density. The solutions, like the previous work, are revealed to be physically interesting and viable models for the explanation of wormholes as far as the background theory and literature are concerned.

Static Traversable Wormholes in f(R,T)=R+2αlnT Gravity

Chinese Journal of Physics

Traversable wormholes, studied by Morris and Thorne in general relativity, are investigated in this research paper in f (R, T ) gravity by introducing a new form of nonlinear f (R, T ) function. By using this novel function, the Einstein's field equations in f (R, T ) gravity are derived. To obtain the exact wormhole solutions, the relations p t = ωρ and p r = sinh(r)p t , where ρ is the energy density, p r is the radial pressure and p t is the tangential pressure, are used. Other than these relations, two forms of shape function defined in literature are used, and their suitability is examined by exploring the regions of validity of null, weak, strong and dominant energy conditions . Consequently, the radius of the throat or the spherical region, with satisfied energy conditions, is determined and the presence of exotic matter is minimized.

Traversable wormholes with logarithmic shape function in f(R,T) gravity

International Journal of Geometric Methods in Modern Physics

In this work, a new form of the logarithmic shape function is proposed for the linear [Formula: see text] gravity, [Formula: see text] where [Formula: see text] is an arbitrary coupling constant, in wormhole geometry. The desired logarithmic shape function accomplishes all necessary conditions for a traversable and asymptotically flat wormhole. The obtained wormhole solutions are analyzed from the energy conditions for different values of [Formula: see text]. It has been observed that our proposed shape function for the linear form of [Formula: see text] gravity, represents the existence of exotic matter and non-exotic matter. Moreover, for [Formula: see text] i.e. for the general relativity case, the existence of exotic matter for the wormhole geometry has been confirmed. Further, the behavior of the radial state parameter [Formula: see text], the tangential state parameter [Formula: see text], and the anisotropy parameter △ describing the geometry of the universe, has been present...

Conformally symmetric traversable wormholes in f(R,T)f(R,T)f(R,T) gravity

arXiv (Cornell University), 2019

To find more deliberate f (R, T) astrophysical solutions, we proceed by studying wormhole geometries under the assumption of spherical symmetry and the existence of a conformal Killing symmetry to attain the more acceptable astrophysical results. To do this, we consider a more plausible and simple model f (R, T) = R + 2χT , where R is the Ricci scalar and T = −ρ + pr + 2pt denotes the trace of the energy-momentum tensor of the matter content. We explore and analyze two cases separately. In the first part, wormhole solutions are constructed for the matter sources with isotropic pressure. However, the obtained solution does not satisfy the required wormhole conditions. In the second part, we introduce an EoS relating to pressure (radial and lateral) and density. We constrain the models with phantom energy EoS i.e. ω = pr/ρ < −1, consequently violating the null energy condition. Next, we analyze the model via pt = npr. Several physical properties and characteristics of these solutions are investigated which are consistent with previous references about wormholes. We mainly focus on energy conditions (NEC, WEC and SEC) and consequently for supporting the respective wormhole geometries in details. In both cases it is found that the energy density is positive as seen by any static observer. To support the theoretical results, we also plotted several figures for different parameter values of the model that helps us to confirm the predictions. Finally, the volume integral quantifier, which provides useful information about the total amount of exotic matter required to maintain a traversable wormhole is discussed briefly.

Traversable wormholes in f(R,T)$f(R,T)$ gravity

Astrophysics and Space Science

In the present article, models of traversable wormholes within the f (R, T) modified gravity theory are investigated. We have presented some wormhole models, developed from various hypothesis for the substance of their matter, i.e. various relationships with their components of pressure (lateral and radial). The solutions found for the shape functions of the wormholes produced complies with the required metric conditions. The suitability of solution is examined by exploring null, strong and dominant energy conditions. It is surmised that the normal matter in the throat may pursue the energy conditions yet the gravitational field exuding from the adjusted gravity hypothesis support the appearance of the non-standard geometries of wormholes.

Study of static wormhole solutions in F(T,TG) gravity

Annals of Physics

In this paper, we investigate static spherically symmetric wormhole solutions in the background of F (T, T G) gravity (T is the torsion scalar and T G represents teleparallel equivalent of the Gauss-Bonnet term). We study the wormhole solutions by assuming four different matter contents, a specific redshift function and a particular F (T, T G) model. The behavior of null/weak energy conditions for these fluids is analyzed graphically. It turns out that wormhole solutions can be obtained in the absence of exotic matter for some particular regions of spacetime. We also explore stability of wormhole solutions through equilibrium condition. It is concluded that there exist physically acceptable wormhole solutions for anisotropic, isotropic and traceless fluids.

Wormhole formation in massive gravity: an analytic description

The European Physical Journal C

The present study analyses the wormhole solution both in the dRGT-f(R, T) massive gravity and Einstein massive gravity. In both the models, the anisotropic pressure solution in ultrastatic wormhole geometry gives rise to the shape function that involves massive gravity parameters gamma\gammagamma γ and Lambda\LambdaLambda Λ . However, the terms consisting of gamma\gammagamma γ and Lambda\LambdaLambda Λ acts in such a way that the spacetime loses asymptotic flatness. Similar to the black hole solution in massive gravity, this inconsistency arises due to the repulsive effect of gravity which can be represented by the photon deflection angle that goes negative after a certain radial distance. It is investigated that the repulsive effect induced in the massive gravitons push the spacetime geometry so strongly that the asymptotic flatness is effected. On the other hand, in this model, one can have a wormhole with ordinary matter at the throat that satisfies all the energy conditions while the negative energ...

Stable Wormholes in the Background of an Exponential f(R) Gravity

Universe, 2020

The current paper is devoted to investigating wormhole solutions with an exponential gravity model in the background of f ( R ) theory. Spherically symmetric static spacetime geometry is chosen to explore wormhole solutions with anisotropic fluid source. The behavior of the traceless matter is studied by employing a particular equation of state to describe the important properties of the shape-function of the wormhole geometry. Furthermore, the energy conditions and stability analysis are done for two specific shape-functions. It is seen that the energy condition are to be violated for both of the shape-functions chosen here. It is concluded that our results are stable and realistic.

Wormholes in kappa(R,T)\kappa(R,T)kappa(R,T) gravity

arXiv (Cornell University), 2022

The wormhole solution could be found by solving the Einstein field equations with violating the null energy condition (NEC). We represent wormhole solutions in κ(R, T) gravity in two different ways. At first, we find the shape function by considering a redshift function and linear equation of state (EoS). The solution represents a wormhole for the real feasible matter. In the second part, we consider four pairs of two redshift functions and two shape functions and analyze the obtained solutions. Some of the models suggest that for particular values of the parameters, the existence of wormholes are supported by an arbitrarily small quantity of exotic matter.