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Related papers: Quantum Dynamics of Lorentzian Spacetime Foam

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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

We consider the generalized Tolman solution of general relativity, describing the evolution of a spherical dust cloud in the presence of an external electric or magnetic field. The solution contains three arbitrary functions $f(R)$, $F(R)$…

General Relativity and Quantum Cosmology · Physics 2021-11-18 Kirill A. Bronnikov , Pavel E. Kashargin , Sergey V. Sushkov

We investigate the role of a specifically warped extra dimension in constructing examples of higher dimensional spacetimes representing Lorentzian wormholes. The warping chosen is largely inspired by the well-known non-static Witten bubble…

General Relativity and Quantum Cosmology · Physics 2022-07-20 Sayan Kar

A model of space-time foam in the form of an arbitrary distribution of spherical Euclidean wormholes is considered. A method for constructing the exact solution of Einstein's Euclidean equations for the metric corresponding to this model is…

General Relativity and Quantum Cosmology · Physics 2024-01-04 A. A. Kirillov , E. P. Savelova

Black bounce spacetimes usually arise from the Simpson-Visser regularization method. This type of metric presents a wormhole throat inside an event horizon. In this paper, we presented new classes of black bounce spacetime solutions, which…

General Relativity and Quantum Cosmology · Physics 2025-02-11 Manuel E. Rodrigues , Marcos V. de S. Silva

In this work, we analyse the evolution of time-dependent traversable wormhole geometries in a Friedmann-Lema\^{i}tre-Robertson-Walker background in the context of the scalar-tensor representation of hybrid metric-Palatini gravity. We deduce…

General Relativity and Quantum Cosmology · Physics 2021-04-06 Mahdi Kord Zangeneh , Francisco S. N. Lobo

The presence of exotic matter for the existence of the wormhole geometry has been an unavoidable problem in GR. In recent studies researchers have tried to deal with this issue using modified gravity theories where the WH geometry is…

General Physics · Physics 2022-04-19 Umesh Kumar Sharma , Shweta , Ambuj Kumar Mishra

It has recently been shown that traversable wormholes may be supported by phantom energy. In this work phantom wormhole geometries are modelled by matching an interior traversable wormhole solution, governed by the equation of state…

General Relativity and Quantum Cosmology · Physics 2009-11-11 Francisco S. N. Lobo

An exact solution is obtained in the tetrad theory of gravitation. This solution is characterized by two-parameters $k_1, k_2$ of spherically symmetric static Lorentzian wormhole which is obtained as a solution of the equation…

General Relativity and Quantum Cosmology · Physics 2007-08-13 Gamal G. L. Nashed

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

We present the first dynamical model of plasma accretion onto traversable wormholes by performing General Relativistic magneto-hydrodynamical (GRMHD) simulations of the flow on both sides of the wormhole. We evolve the ideal MHD equations…

High Energy Astrophysical Phenomena · Physics 2024-05-14 Luciano Combi , Huan Yang , Eduardo Gutierrez , Scott C. Noble , Gustavo E. Romero , Manuela Campanelli

In this paper, we discuss the thermodynamic properties of the evolving Lorentzian wormhole. For the shape function $b(r) = r_{0}^2/r$, it is shown that the wormhole spacetime admits two apparent horizons, the inner and the outer one. The…

High Energy Physics - Theory · Physics 2009-11-16 Mubasher Jamil , M. Akbar

A general formalism for the dynamics of non rotating cylindrical thin-shell wormholes is developed. The time evolution of the throat is explicitly obtained for thin-shell wormholes whose metric has the form associated to local cosmic…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Ernesto F. Eiroa , Claudio Simeone

It is shown that the general solution of classical equations of motion in two dimensional dilaton gravity proposed by Callan, Giddings, Harvey and Strominger (CGHS) includes a Lorentzian wormhole solution in addition to a black hole…

High Energy Physics - Theory · Physics 2009-10-22 Shin'ichi Nojiri , I. Oda

In the studies of quantum field theory in curved spacetime, the ambiguous concept of vacuum state and the particle content is a long-standing debatable aspect. So far it is well known to us that in the background of the curved spacetime,…

General Relativity and Quantum Cosmology · Physics 2019-10-16 Ashmita Das , Surojit Dalui , Chandramouli Chowdhury , Bibhas Ranjan Majhi

We investigate the propagation of the scalar waves in the Witten space-time called "bubble of nothing" and in its remarkable sub-manifold, the Lorentzian Hawking wormhole. Due to the global hyperbolicity, the global Cauchy problem is…

Mathematical Physics · Physics 2017-04-05 Alain Bachelot

In this work, we find exact wormhole solutions in the context of noncommutative geometry, and further explore their physical properties and characteristics. The energy density of these wormhole geometries is a smeared and particle-like…

General Relativity and Quantum Cosmology · Physics 2008-12-23 Remo Garattini , Francisco S. N. Lobo

We show that Lorentzian (traversable) wormholes and time machines with semi-classical spacetimes are unstable due to their violation of the null energy condition (NEC). Semi-classicality of the energy-momentum tensor in a given quantum…

High Energy Physics - Theory · Physics 2009-11-11 Roman V. Buniy , Stephen D. H. Hsu

It has been suggested that the cosmological constant is a variable dynamical quantity. A class of solution has been presented for the spherically symmetric space time describing wormholes by assuming the erstwhile cosmological constant…

General Relativity and Quantum Cosmology · Physics 2008-11-26 F. Rahaman , M. Kalam , M. Sarker , A. Ghosh , B. Raychaudhuri

We give a partial answer to the question whether the Schrodinger equation can be derived from the Newtonian mechanics of a particle in a potential subject to a random force. We show that the fluctuations around the classical motion of a one…

Quantum Physics · Physics 2021-02-24 Can Gokler
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