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All known solutions to the Einstein equations describing rotating cylindrical wormholes lack asymptotic flatness and therefore cannot describe wormhole entrances as local objects in our Universe. To overcome this difficulty, wormhole…

General Relativity and Quantum Cosmology · Physics 2019-05-13 K. A. Bronnikov , V. G. Krechet

In this paper, we explore wormhole solutions in a higher-derivative theory of gravity where the action depends not only on the Ricci scalar \(R\), but also on its d'Alembertian, \(\Box R\). Such \(f(R,\Box R)\) models are motivated by…

General Relativity and Quantum Cosmology · Physics 2026-05-19 M Daniel Ranjan , Soumya Chakrabarti , Sanjit Das

We obtain a large class of Lorentzian wormhole spacetimes in scalar-tensor gravity, for which the matter stress energy does satisfy the weak energy condition. Our constructions have zero Ricci scalar and an everywhere finite, non-zero…

General Relativity and Quantum Cosmology · Physics 2016-07-12 Rajibul Shaikh , Sayan Kar

In the context of General Relativity (GR), violation of the null energy condition (NEC) is necessary for existence of static spherically symmetric wormhole solutions. Also, it is a well-known fact that the energy conditions are violated by…

General Relativity and Quantum Cosmology · Physics 2024-11-19 Mohammad Reza Mehdizadeh , Amir Hadi Ziaie

We present a traversable wormhole solution using the traceless $f(R,T)$ theory of gravity. In the $f(R,T)$ gravity, the Ricci scalar $R$ in the Einstein-Hilbert action is replaced by a function of $R$ and trace of the energy momentum tensor…

General Relativity and Quantum Cosmology · Physics 2021-09-02 Parbati Sahoo , P. H. R. S. Moraes , Marcelo M. Lapola , P. K. Sahoo

We discuss several properties of static, spherically symmetric wormholes with particular emphasis on the behavior of causal geodesics and the propagation of linear fields. We show there always exist null geodesics which are trapped in a…

General Relativity and Quantum Cosmology · Physics 2014-06-17 Olivier Sarbach , Thomas Zannias

In this work we analyze traversable wormhole spacetimes in the framework of a covariant generalization of Einstein's General Relativity known as energy-momentum squared gravity, or $f\left(R,\mathcal T\right)$ gravity, where $R$ is the…

General Relativity and Quantum Cosmology · Physics 2023-11-16 João Luís Rosa , Nailya Ganiyeva , Francisco S. N. Lobo

In this work, we investigate static and spherically symmetric traversable wormhole solutions within the framework of the extended symmetric teleparallel gravity, specifically the $\mathcal{F}(Q,\mathcal{L}_{m},\mathcal{T})$ gravity theory,…

General Relativity and Quantum Cosmology · Physics 2025-07-15 Rounak Manna , Krishna Pada Das , Ujjal Debnath

This paper examines wormhole geometries in the context of $f(Q,T)$ gravity under the background of non-commutative distributions. We discuss the analytical solutions assuming spherical symmetry and the presence of conformal Killing vectors,…

General Relativity and Quantum Cosmology · Physics 2024-03-22 Moreshwar Tayde , Zinnat Hassan , P. K. Sahoo

We present here analytical solutions of General Relativity that describe evolving wormholes with a non-constant redshift function. We show that the matter that threads these wormholes is not necessarily exotic. Finally, we investigate some…

General Relativity and Quantum Cosmology · Physics 2009-10-30 Luis A. Anchordoqui , Diego F. Torres , Marta L. Trobo , Santiago E. Perez Bergliaffa

In this paper, exact wormhole solutions in the context of $f(R)$ theory of gravity are investigated. Since the Einstein field equations are modified in 3+1 dimensions in the $f(R)$ theory of gravity, we have studied some possible solutions…

General Relativity and Quantum Cosmology · Physics 2021-10-15 Foad Parsaei , Sara Rastgoo

In this talk I discuss pertinence of the wormholes to the problem of circumventing the light speed barrier and present a specific class of wormholes. The wormholes of this class are static and have arbitrarily wide throats, which makes them…

General Relativity and Quantum Cosmology · Physics 2007-05-23 S. V. Krasnikov

Wormhole geometries in curvature-matter coupled modified gravity are explored, by considering an explicit nonminimal coupling between an arbitrary function of the scalar curvature, R, and the Lagrangian density of matter. It is the…

General Relativity and Quantum Cosmology · Physics 2010-11-09 Nadiezhda Montelongo Garcia , Francisco S. N. Lobo

We seek wormholes among rotating cylindrically symmetric configurations in general relativity. Exact wormhole solutions are presented with such sources of gravity as a massless scalar field, a cosmological constant, and a scalar field with…

General Relativity and Quantum Cosmology · Physics 2016-03-30 K. A. Bronnikov , V. G. Krechet

We derive a shortcut stationary metric formula for generating imperfect fluid rotating solutions, in Boyer-Lindquist coordinates, from spherically symmetric static ones. We explore the properties of the curvature scalar and stress-energy…

General Relativity and Quantum Cosmology · Physics 2014-05-12 Mustapha Azreg-Aïnou

Some recent papers have claimed the existence of static, spherically symmetric wormhole solutions to gravitational field equations in the absence of ghost (or phantom) degrees of freedom. We show that in some such cases the solutions in…

General Relativity and Quantum Cosmology · Physics 2014-11-21 K. A. Bronnikov , M. V. Skvortsova , A. A. Starobinsky

We study the properties of evolving wormholes able to exist in a closed Friedmann dust-filled universe and described by a particular branch of the well-known Lema{\i}tre-Tolman-Bondi solution to the Einstein equations and its generalization…

General Relativity and Quantum Cosmology · Physics 2023-11-14 Kirill A. Bronnikov , Pavel E. Kashargin , Sergey V. Sushkov

A possible astrophysical object to be found in General Relativity is the wormhole. This special solution describes a topological bridge connecting points in two distinguished universes or two different points in the same universe. Despite…

General Relativity and Quantum Cosmology · Physics 2023-06-21 Moreshwar Tayde , Joao R. L. Santos , Julia N. Araujo , P. K. Sahoo

We find the static spherically symmetric solutions (with vanishing shift function) of the complete nonprojectable Horava theory explicitly, writing the space-time metrics as explicit tensors in local coordinate systems. This completes…

General Relativity and Quantum Cosmology · Physics 2014-08-25 Jorge Bellorin , Alvaro Restuccia , Adrian Sotomayor

Exact solutions of Einstein equations with null Riemman-Christoffel curvature tensor everywhere, except on a hypersurface, are studied using quantum particles obeying the Klein-Gordon equation. We consider the particular cases when the…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Paulo M. Pitelli , Patricio S. Letelier