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In the present paper, we investigate wormholes in 4D-Einstein-Gauss-Bonnet gravity without the requirement of exotic matters. We have taken the radial dependent red-shift function $\phi=\ln \left( {\frac {r_{{0}}}{r}}+1 \right)$ and shape…

General Relativity and Quantum Cosmology · Physics 2022-11-23 Ambuj Kumar Mishra , Shweta , Umesh Kumar Sharma

Recent studies have shown that (a) quantum effects may be sufficient to support a wormhole throat and (b) the total amount of "exotic matter" can be made arbitrarily small. Unfortunately, using only small amounts of exotic matter may result…

General Relativity and Quantum Cosmology · Physics 2009-11-10 Peter K. F. Kuhfittig

In the conventional method of studying wormhole (WH) geometry, traversability requires the presence of exotic matter, which also provides negative gravity effects to keep the wormhole throat open. In dRGT massive gravity theory, we produce…

General Relativity and Quantum Cosmology · Physics 2024-08-07 Piyali Bhar

A wormhole is constructed by cutting and joining two spacetimes satisfying the low energy string equations with a dilaton field. In spacetimes described by the "string metric" the dilaton energy-momentum tensor need not satisfy the weak or…

General Relativity and Quantum Cosmology · Physics 2010-11-19 Dan N. Vollick

Various spacetime candidates for traversable wormholes, regular black holes, and `black-bounces' are presented and thoroughly explored in the context of the gravitational theory of general relativity. All candidate spacetimes belong to the…

General Relativity and Quantum Cosmology · Physics 2021-04-30 Alex Simpson

This paper addresses the following issues: (1) the possible existence of macroscopic traversable wormholes, given a noncommutative-geometry background, and (2) the possibility of allowing zero tidal forces, given a known density. It is…

General Relativity and Quantum Cosmology · Physics 2019-01-09 Peter K. F. Kuhfittig

Traversible wormhole space-times are found as static, spherically symmetric solutions to the Einstein equations with ingoing and outgoing pure ghost radiation, i.e. pure radiation with negative energy density. Switching off the radiation…

General Relativity and Quantum Cosmology · Physics 2009-11-07 Sean A. Hayward

We have found a simple exact solution of spherically-symmetrical Einstein equations describing a wormhole for an inhomogeneous distribution of the phantom energy. The equation of state is linear but highly anisotropic: while the radial…

General Relativity and Quantum Cosmology · Physics 2009-11-11 O. B. Zaslavskii

A possible cause of the late-time cosmic acceleration is an exotic fluid with an equation of state lying within the phantom regime, i.e., $w=p/\rho <-1$. The latter violates the null energy condition, which is a fundamental ingredient in…

General Relativity and Quantum Cosmology · Physics 2013-04-12 Francisco S. N. Lobo , Foad Parsaei , Nematollah Riazi

Noncommutative geometry, an offshoot of string theory, replaces point-like particles by smeared objects. These local effects have led to wormhole solutions in a semiclassical setting, but it has also been claimed that the noncommutative…

General Relativity and Quantum Cosmology · Physics 2024-12-24 Peter K. F. Kuhfittig

This paper studies wormhole solutions to Einstein gravity with an arbitrary number of time dependent compact dimensions and a matter-vacuum boundary. A new gauge is utilized which is particularly suited for studies of the wormhole throat.…

General Relativity and Quantum Cosmology · Physics 2009-11-07 A. DeBenedictis , A. Das

The wormhole solution could be found by solving the Einstein field equations with violating the null energy condition (NEC). We represent wormhole solutions in $\kappa(R,T)$ gravity in two different ways. At first, we find the shape…

General Relativity and Quantum Cosmology · Physics 2022-07-27 Susmita Sarkar , Nayan Sarkar , Farook Rahaman , Y Aditya

The model of a spiral galaxy with radially directed flows of dark matter is extended by exotic matter, in a form of a perfect fluid with a linear anisotropic equation of state. The exotic matter is collected in the minimum of gravitational…

General Relativity and Quantum Cosmology · Physics 2017-07-11 Igor Nikitin

The study of traversable wormholes is very hot topic for the past 30 years. One of the best possible way to make traversable wormhole is using the thin-shells to cut and paste two spacetime which has tunnel from one region of space-time to…

General Relativity and Quantum Cosmology · Physics 2016-10-27 Ali Övgün

We consider Non-local Gravity in view to obtain stable and traversable wormhole solutions. In particular, the class of Non-local Integral Kernel Theories of Gravity, with the inverse d'Alembert operator in the gravitational action, is taken…

General Relativity and Quantum Cosmology · Physics 2022-11-28 Salvatore Capozziello , Nisha Godani

We consider stationary, cylindrically symmetric configurations in general relativity and formulate necessary conditions for the existence of rotating cylindrical wormholes. It is shown that in a comoving reference frame the rotational part…

General Relativity and Quantum Cosmology · Physics 2013-09-12 Kirill A. Bronnikov , Vladimir G. Krechet , José P. S. Lemos

In this work, we investigate wormhole solutions through the utilization of gravitational decoupling, employing the Minimal Geometric Deformation (MGD) procedure within the framework of Trace-Free Gravity. We base our investigation on static…

General Relativity and Quantum Cosmology · Physics 2024-05-17 Piyachat Panyasiripan , Narakorn Kaewkhao , Phongpichit Channuie , Ali Övgün

The solutions of traversable wormholes and their geometries are investigated in higher-curvature gravity with boundary terms for each case under the presence of anisotropic, isotropic and barotropic fluids in detail. For each case, the…

General Relativity and Quantum Cosmology · Physics 2023-10-03 M. Ilyas , Kazuharu Bamba

We consider $f(R, T)$ theory of gravity, in which the gravitational Lagrangian is given by an arbitrary function of the Ricci scalar and the trace of the energy-momentum tensor, to study static spherically symmetric wormhole geometries…

General Relativity and Quantum Cosmology · Physics 2021-08-03 Ayan Banerjee , M. K. Jasim , Sushant G. Ghosh

It is known that static traversable wormhole in Einstein gravity is supported by matter that violates null energy conditions (NEC). Essentially such wormhole will be characterised by a central throat with anisotropic matter lining the…

General Relativity and Quantum Cosmology · Physics 2023-05-17 Subhra Bhattacharya , Subhasis Nalui