scholarly journals On the Stability of Thin-Shell Wormholes in Noncommutative Geometry

2012 ◽  
Vol 2012 ◽  
pp. 1-12 ◽  
Author(s):  
Peter K. F. Kuhfittig

This paper reexamines a special class of thin-shell wormholes that are unstable in general relativity in the framework of noncommutative geometry. It is shown that, as a consequence of the intrinsic uncertainty, these wormholes are stable to small linearized radial perturbations. Several different spacetimes are considered.

2018 ◽  
Vol 33 (09) ◽  
pp. 1850049 ◽  
Author(s):  
Z. Amirabi ◽  
M. Halilsoy ◽  
S. Habib Mazharimousavi

At the Planck scale of length [Formula: see text] m where the energy is comparable with the Planck energy, the quantum gravity corrections to the classical background spacetime results in gravity’s rainbow or rainbow gravity. In this modified theory of gravity, geometry depends on the energy of the test particle used to probe the spacetime, such that in the low energy limit, it yields the standard general relativity. In this work, we study the thin-shell wormholes in the spherically symmetric rainbow gravity. We find the corresponding properties in terms of the rainbow functions which are essential in the rainbow gravity and the stability of such thin-shell wormholes are investigated. Particularly, it will be shown that there are exact solutions in which high energy particles crossing the throat will encounter less amount of total exotic matter. This may be used as an advantage over general relativity to reduce the amount of exotic matter.


2008 ◽  
Vol 17 (08) ◽  
pp. 1179-1196 ◽  
Author(s):  
MARTÍN G. RICHARTE ◽  
CLAUDIO SIMEONE

We study spherically symmetric thin shell wormholes in a string cloud background in (3 + 1)-dimensional space–time. The amount of exotic matter required for the construction, the traversability and the stability of such wormholes under radial perturbations are analyzed as functions of the parameters of the model. In addition, in the appendices a nonperturbative approach to the dynamics and a possible extension of the analysis to a related model are briefly discussed.


2015 ◽  
Vol 24 (05) ◽  
pp. 1550034 ◽  
Author(s):  
Piyali Bhar ◽  
Ayan Banerjee

In this paper, we construct thin-shell wormholes in (2 + 1)-dimensions from noncommutative BTZ black hole by applying the cut-and-paste procedure implemented by Visser. We calculate the surface stresses localized at the wormhole throat by using the Darmois–Israel formalism and we find that the wormholes are supported by matter violating the energy conditions. In order to explore the dynamical analysis of the wormhole throat, we consider that the matter at the shell is supported by dark energy equation of state (EoS) p = ωρ with ω < 0. The stability analysis is carried out of these wormholes to linearized spherically symmetric perturbations around static solutions. Preserving the symmetry we also consider the linearized radial perturbation around static solution to investigate the stability of wormholes which was explored by the parameter β (speed of sound).


2020 ◽  
Vol 29 (01) ◽  
pp. 2050007 ◽  
Author(s):  
M. Sharif ◽  
Faisal Javed

This paper investigates the effects of charge on linearized stability of rotating thin-shell wormholes (WHs) filled with a barotropic fluid. We use Visser cut and paste technique to construct thin-shell from charged rotating Bañados–Teitelboim–Zanelli (BTZ) black holes (BHs). The components of stress-energy tensor are evaluated through Israel thin-shell formalism. The angular momentum for both interior as well as exterior region at the WH throat remains the same but opposite in direction, i.e. thin-shell WH at the throat is counter-rotated. It is found that the geometrical structure of WHs is more stable for highly charged and fast rotating thin-shell. We conclude that the stability regions of charged rotating WHs are larger than the uncharged rotating WHs.


2016 ◽  
Vol 2016 ◽  
pp. 1-13 ◽  
Author(s):  
M. Sharif ◽  
Saadia Mumtaz

The aim of this paper is to construct regular Hayward thin-shell wormholes and analyze their stability. We adopt Israel formalism to calculate surface stresses of the shell and check the null and weak energy conditions for the constructed wormholes. It is found that the stress-energy tensor components violate the null and weak energy conditions leading to the presence of exotic matter at the throat. We analyze the attractive and repulsive characteristics of wormholes corresponding toar>0andar<0, respectively. We also explore stability conditions for the existence of traversable thin-shell wormholes with arbitrarily small amount of fluid describing cosmic expansion. We find that the space-time has nonphysical regions which give rise to event horizon for0<a0<2.8and the wormhole becomes nontraversable producing a black hole. The nonphysical region in the wormhole configuration decreases gradually and vanishes for the Hayward parameterl=0.9. It is concluded that the Hayward and Van der Waals quintessence parameters increase the stability of thin-shell wormholes.


2020 ◽  
Vol 35 (02n03) ◽  
pp. 2040015
Author(s):  
Muhammad Sharif ◽  
Faisal Javed

This work is devoted to exploring the stability of thin-shell wormholes developed from two equivalent copies of charged quintessence (charged Kiselev) black holes by using Visser cut and paste approach. The characteristics of the surface matter of the shell are determined by using Israel formalism. We examine the stability of thin-shell by assuming a barotropic equation of state for the surface matter of the wormhole throat. We conclude that wormhole becomes stable in the presence of both charge and Kiselev parameter otherwise, it shows an unstable behavior.


2020 ◽  
Vol 80 (8) ◽  
Author(s):  
Takol Tangphati ◽  
Auttakit Chatrabhuti ◽  
Daris Samart ◽  
Phongpichit Channuie

Abstract In this work, we study the thin-shell wormholes in dRGT massive gravity. In order to glue two bulks of the spacetime geometry, we first derive junction conditions of the dRGT spacetime. We obtain the dynamics of the spherical thin-shell wormholes in the dRGT theory. We show that the massive graviton correction term of the dRGT theory in the Einstein equation is represented in terms of the effective anisotropic pressure fluid. However, if there is only this correction term, without invoking exotic fluids, we find that the thin-shell wormholes cannot be stabilized. We then examine the stability conditions of the wormholes by introducing four existing models of the exotic fluids at the throat. In addition, we analyze the energy conditions for the thin-shell wormholes in the dRGT massive gravity by checking the null, weak, and strong conditions at the wormhole throat. We show that in general the classical energy conditions are violated by introducing all existing models of the exotic fluids. Moreover, we quantify the wormhole geometry by using the embedding diagrams to represent a thin-shell wormhole in the dRGT massive gravity.


2020 ◽  
Vol 35 (37) ◽  
pp. 2050309
Author(s):  
Faisal Javed ◽  
M. Sharif

This paper explores the stable configuration of thin-shell wormholes constructed from two regular black holes (modified Hayward and four parametric) by using Visser cut and paste approach. The components of stress-energy tensor are evaluated through the Lanczos equations. We analyze the stability of thin-shell by using radial perturbation preserving its symmetries about equilibrium static solution. It is found that modified Hayward wormholes are more stable than the Hayward wormholes. Further, the stable regions of four parametric regular wormholes are larger than the Schwarzschild, Reissner–Nordström and Ayón–Beato–García wormholes. We conclude that stable region decreases for highly charged thin-shell wormholes.


2019 ◽  
Vol 35 (09) ◽  
pp. 2050059
Author(s):  
Peter K. F. Kuhfittig ◽  
Vance D. Gladney

Noncommutative geometry, an offshoot of string theory, replaces point-like objects by smeared objects. The resulting uncertainty may cause a black hole to be observationally indistinguishable from a traversable wormhole, while the latter, in turn, may become observationally indistinguishable from a gravastar. The same noncommutative-geometry background allows the theoretical construction of thin-shell wormholes from gravastars and may even serve as a model for dark energy.


2017 ◽  
Vol 26 (05) ◽  
pp. 1741007 ◽  
Author(s):  
Muhammad Sharif ◽  
Saadia Mumtaz

This work is devoted to investigate the stability of thin-shell wormholes in Einstein–Hoffmann–Born–Infeld electrodynamics. We also study the attractive and repulsive characteristics of these configurations. A general equation-of-state is considered in the form of linear perturbation which explores the stability of the respective wormhole solutions. We assume Chaplygin, linear and logarithmic gas models to study exotic matter at thin-shell and evaluate stability regions for different values of the involved parameters. It is concluded that the Hoffmann–Born–Infeld parameter and electric charge enhance the stability regions.


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