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In this paper, we analyze the Schwarzschild-like wormhole in the Asymptotically Safe Gravity(ASG) scenario. The ASG corrections are implemented via renormalization group methods, which, as consequence, provides a new tensor $X_{\mu\nu}$ as…

General Relativity and Quantum Cosmology · Physics 2021-10-12 M. Nilton , G. Alencar

A class of wormhole solutions is constructed that has restricted polar degrees of freedom to achieve a gateway-like configuration. This compels the use of distribution-valued metrics and connections which further compels the use of neutrix…

General Relativity and Quantum Cosmology · Physics 2023-03-22 Abhishek Kumar Mehta

We reformulate the construction of wormhole solutions as perturbations around near-horizon geometries of near-extremal Reissner-Nordstr\"{o}m black holes in four dimensions and equal-angular-momenta Myers-Perry black holes in five…

General Relativity and Quantum Cosmology · Physics 2025-11-27 Takamasa Kanai , Kengo Maeda , Daisuke Yoshida

A Regge--Wheeler analysis is performed for a novel black hole mimicker `the regular black hole with asymptotically Minkowski core', followed by an approximation of the permitted quasi-normal modes for propagating waveforms. A first-order…

General Relativity and Quantum Cosmology · Physics 2021-10-06 Alex Simpson

We study spherically symmetric, self-similar wormhole solutions supported by colliding streams of negative-energy null dust, and their dynamical formation. Under the assumption of self-similarity, the Einstein equations reduce to a system…

General Relativity and Quantum Cosmology · Physics 2026-02-17 Yasutaka Koga , Ryota Maeda , Daiki Saito , Daisuke Yoshida

A model of traversable wormhole in an extended gravity theory has been proposed. The Casimir effect and Generalised Uncertainty Principle (GUP) arising out of the concept of minimal length have been considered to obtain the shape function,…

General Relativity and Quantum Cosmology · Physics 2020-12-16 S K Tripathy

An important question about black holes is to what extent a typical pure state differs from the ensemble average. We show that this question can be answered within semi-classical gravity. We focus on the quantum deviation, which measures…

High Energy Physics - Theory · Physics 2023-03-08 Ben Freivogel , Dora Nikolakopoulou , Antonio F. Rotundo

We describe two interesting effects in wormhole physics. First, we find that a genuinely charged matter source may appear neutral to an external observer - a phenomenon opposite to the famous Misner-Wheeler "charge without charge" effect.…

High Energy Physics - Theory · Physics 2015-05-30 Eduardo Guendelman , Alexander Kaganovich , Emil Nissimov , Svetlana Pacheva

We calculate the Casimir energy-momentum tensor induced in a scalar field by a macroscopic ultrastatic spherically-symmetric long-throated traversable wormhole, and examine whether this exotic matter is sufficient to stabilise the wormhole…

General Relativity and Quantum Cosmology · Physics 2014-07-09 Luke M. Butcher

A one-parameter family of static and spherically symmetric solutions to Einstein equations with a traceless energy-momentum tensor is found. When the nonzero parameter $\beta$ lies in the open interval $(0,1)$ one obtains traversable…

General Relativity and Quantum Cosmology · Physics 2010-11-11 A. G. Agnese , M. La Camera

Motivated by bulk replica wormholes, we study the boundary effective theory that describes the near-horizon fluctuations of a near-extremal Reissner-Nordstr\"om black hole. This theory consists of a Schwarzian mode and a $U(1)$ phase mode.…

High Energy Physics - Theory · Physics 2026-04-30 Jun Nian , Yuan Zhong

We build spherically symmetric wormholes within the DGP theory. We calculate the energy localized on the shell, and we find that for certain values of the parameters wormholes could be supported by matter not violating the energy…

General Relativity and Quantum Cosmology · Physics 2015-03-17 Martín G. Richarte

In this work wormholes in viable $f(R)$ gravity models are analysed. We are interested in exact solutions for stress-energy tensor components depending on different shape and redshift functions. Several solutions of gravitational equations…

General Relativity and Quantum Cosmology · Physics 2015-03-24 Petar Pavlović , Marko Sossich

This work is devoted to the study of analytic wormhole solutions within the framework of $f(R)$ gravity theory. To check the possibility of having wormhole structures satisfying energy conditions, by means of the class I approach the pair…

General Relativity and Quantum Cosmology · Physics 2022-06-09 A. S. Agrawal , B. Mishra , Francisco Tello-Ortiz , A. Alvarez

In this paper we show that wormholes in (2+1) dimensions (3-D) cannot be sourced solely by both Casimir energy and tension, differently from what happens in a 4-D scenario, in which case it has been shown recently, by the direct computation…

General Relativity and Quantum Cosmology · Physics 2021-11-03 G. Alencar , V. B. Bezerra , C. R. Muniz

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…

General Relativity and Quantum Cosmology · Physics 2016-10-31 Piyali Bhar , Ayan Banerjee

The Casimir energy of a semi-circular cylindrical shell is calculated by making use of the zeta function technique. This shell is obtained by crossing an infinite circular cylindrical shell by a plane passing through the symmetry axes of…

High Energy Physics - Theory · Physics 2009-10-31 V. V. Nesterenko , G. Lambiase , G. Scarpetta

We assume the space-time foam picture in which the vacuum is filled with a gas of virtual wormholes. It is shown that virtual wormholes form a finite (of the Planckian order) value of the energy density of zero-point fluctuations. However…

Cosmology and Nongalactic Astrophysics · Physics 2013-06-25 A. A. Kirillov , E. P. Savelova

Quantum mechanical concept such as the Casimir effect is explored to model traversable wormholes in an extended teleparallel gravity theory. The minimal length concept leading to the generalized uncertainty principle (GUP) is used to obtain…

General Relativity and Quantum Cosmology · Physics 2024-04-09 Abhilipsa Sahoo , S. K. Tripathy , B. Mishra , Saibal Ray

We propose a unique stellar model under the $f(R,\mathcal{T})$ gravity by using the conjecture of Mazur-Mottola [P. Mazur and E. Mottola, Report number: LA-UR-01-5067., P. Mazur and E. Mottola, Proc. Natl. Acad. Sci. USA 101, 9545 (2004)]…

General Relativity and Quantum Cosmology · Physics 2017-06-14 Amit Das , Shounak Ghosh , B. K. Guha , Swapan Das , Farook Rahaman , Saibal Ray
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