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Related papers: Trace anomaly contributions to semi-classical worm…

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The trace anomaly of quantum fields in electromagnetic or gravitational backgrounds implies the existence of massless scalar poles in physical amplitudes involving the stress-energy tensor. Considering first the axial anomaly and using QED…

High Energy Physics - Theory · Physics 2010-05-27 Maurizio Giannotti , Emil Mottola

We study wormhole solutions in the framework of f (R,T) gravity where R is the scalar curvature, and T is the trace of the stress-energy tensor of the matter. We have obtained the shape function of the wormhole by specifying an equation of…

General Relativity and Quantum Cosmology · Physics 2014-01-30 Tahereh Azizi

Exact solutions of traversable wormholes were recently found under the assumption of spherical symmetry and the existence of a non-static conformal symmetry. In this paper, we verify that in the case of the conformally symmetric spacetimes…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Christian G. Boehmer , Tiberiu Harko , Francisco S. N. Lobo

In the present work, we seek for static spherically symmetric solutions representing wormhole configurations in generalized Rastall gravity (GRG). In this theory, a varying coupling parameter could act as dark energy (DE) and thus, it can…

General Relativity and Quantum Cosmology · Physics 2025-04-08 Naser Sadeghnezhad

We investigate static and spherically symmetric traversable wormhole solutions in the framework of $f(Q)$ gravity by considering a power-law model of the form $f(Q)=\gamma(-Q)^m$. By adopting an anisotropic matter distribution and imposing…

General Relativity and Quantum Cosmology · Physics 2026-05-11 Jaydeep Goswami , Rupam Jyoti Borah , Umananda Dev Goswami

Static solutions representing wormhole configurations in Einstein-Cartan theory ({{\sf ECT}}) in the presence of electric charge are obtained. The solutions are described by a constant redshift function with matter content consisting of a…

General Relativity and Quantum Cosmology · Physics 2019-03-26 Mohammad Reza Mehdizadeh , Amir Hadi Ziaie

We study wormhole geometries embedded in an expanding universe within a four-scalar non-linear $\sigma$ model, where the target-space metric is identified with the spacetime Ricci tensor. In this framework, wormholes can remain stable even…

General Relativity and Quantum Cosmology · Physics 2026-01-16 Taishi Katsuragawa , Shin'ichi Nojiri , Sergei D. Odintsov

This study explores the potential existence of traversable wormholes influenced by a global monopole charge within the $f(Q)$ gravity framework. To elucidate the characteristics of these wormholes, we conducted a comprehensive analysis of…

General Relativity and Quantum Cosmology · Physics 2024-06-26 Moreshwar Tayde , P. K. Sahoo

In this paper, we explore higher-dimensional asymptotically flat wormhole geometries in the framework of Gauss-Bonnet (GB) gravity and investigate the effects of the GB term, by considering a specific radial-dependent redshift function and…

General Relativity and Quantum Cosmology · Physics 2015-04-06 Mohammad Reza Mehdizadeh , Mahdi Kord Zangeneh , Francisco S. N. Lobo

The C-metric in vacuum general relativity describes a pair of accelerated black holes supported by conical singularity. In this paper, we present a new family of exact solutions to the Einstein-phantom scalar system that describes…

General Relativity and Quantum Cosmology · Physics 2023-09-20 Masato Nozawa , Takashi Torii

Properties of $n(\ge 5)$-dimensional static wormhole solutions are investigated in Einstein-Gauss-Bonnet gravity with or without a cosmological constant $\Lambda$. We assume that the spacetime has symmetries corresponding to the isometries…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Hideki Maeda , Masato Nozawa

We investigate the waveforms and quasi-normal modes around Schwarzschild traversable wormholes under different field perturbations, including the scalar field, the electromagnetic (vector) field, and the axial gravitational (tensor) field…

General Relativity and Quantum Cosmology · Physics 2025-07-08 Hao Yang , Zhong-Wu Xia , Yan-Gang Miao

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…

General Relativity and Quantum Cosmology · Physics 2020-08-21 Ayan Banerjee , Ksh. Newton Singh , M. K. Jasim , Farook Rahaman

The time evolution of the field perturbations in the wormhole and black bounce backgrounds are investigated. We find that the asymmetry of spacetime results in the asymmetry of the effective potential of the perturbed equation. The…

General Relativity and Quantum Cosmology · Physics 2022-06-01 Min-Yan Ou , Meng-Yun Lai , Hyat Huang

We use static solutions of 5-dimensional Kaluza-Klein gravity to generate several classes of static, spherically symmetric spacetimes which are analytic solutions to the equation $^{(4)}R = 0$, where $^{(4)}R$ is the four-dimensional Ricci…

General Relativity and Quantum Cosmology · Physics 2010-02-18 J. Ponce de Leon

When bosonic matter in the form of a complex scalar field is added to Ellis wormholes, the phenomenon of spontaneous symmetry breaking is observed. Symmetric solutions possess full reflection symmetry with respect to the radial coordinate…

General Relativity and Quantum Cosmology · Physics 2017-04-12 Christian Hoffmann , Theodora Ioannidou , Sarah Kahlen , Burkhard Kleihaus , Jutta Kunz

We consider novel wormhole solutions supported by a matter content that minimally violates the null energy condition. More specifically, we consider an equation of state in which the sum of the energy density and radial pressure is…

General Relativity and Quantum Cosmology · Physics 2014-11-10 Mariam Bouhmadi-Lopez , Francisco S. N. Lobo , Prado Martin-Moruno

Spacetime wormholes are evidently an essential component of the construction of a time machine. Within the context of general relativity, such objects require, for their formation, exotic matter -- matter that violates at least one of the…

General Relativity and Quantum Cosmology · Physics 2024-06-13 Mengqi Lu , Jiayue Yang , Robert B. Mann

In 6D general relativity with a scalar field as a source of gravity, a new type of static wormhole solutions is presented: such wormholes connect our universe with a small 2D extra subspace with a universe where this extra subspace is…

General Relativity and Quantum Cosmology · Physics 2016-12-07 K. A. Bronnikov , M. V. Skvortsova

There are a number of reasons to study wormholes with generic cosmological constant $\Lambda$. Recent observations indicate that present accelerating expansion of the universe demands $\Lambda>0$. On the other hand, some extended theories…

General Relativity and Quantum Cosmology · Physics 2015-11-24 Y. Heydarzade , N. Riazi , H. Moradpour
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