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Related papers: How Spacetime Foam modifies the brick wall

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Time evolution of a black hole lattice universe is simulated. The vacuum Einstein equations in a cubic box with a black hole at the origin are numerically solved with periodic boundary conditions on all pairs of opposite faces. Defining…

General Relativity and Quantum Cosmology · Physics 2013-10-30 Chul-Moon Yoo , Hirotada Okawa , Ken-ichi Nakao

Spacetime foam is analyzed within the simplistic model of a set of scalar fields on a flat background. We suggest the formula for the path integral which allows to account for the all possible topologies of spacetime. We show that the…

General Relativity and Quantum Cosmology · Physics 2008-09-11 A. A. Kirillov , E. P. Savelova

We argue that a microscopic structure for space-time such as that expected in a quantum foam scenario, in which microscopic wormholes and other topological structures should play a relevant role, might lead to an effective metric-affine…

High Energy Physics - Theory · Physics 2015-06-15 Francisco S. N. Lobo , Gonzalo J. Olmo , D. Rubiera-Garcia

Quantum field theory in the near-horizon region of a black hole predicts the existence of an infinite number of degenerate modes. Such a degeneracy is regulated in the brick wall model by the introduction of a short distance cutoff. In this…

High Energy Physics - Theory · Physics 2009-11-10 Kumar S. Gupta , Siddhartha Sen

The effects that the present accelerating expansion of the universe has on the size and shape of Lorentzian wormholes and ringholes are considered. It is shown that, quite similarly to how it occurs for inflating wormholes, relative to the…

Astrophysics · Physics 2009-11-10 Pedro F. Gonzalez-Diaz

A simple model of spacetime foam, made by N wormholes in a semiclassical approximation, is taken under examination. The Casimir-like energy of the quantum fluctuation of such a model and its probability of being realized are computed.…

General Relativity and Quantum Cosmology · Physics 2014-11-17 Remo Garattini

An effective model for the spacetime foam is constructed in terms of nonlocal interactions in a classical background. In the weak-coupling approximation, the evolution of the low-energy density matrix is determined by a master equation that…

General Relativity and Quantum Cosmology · Physics 2009-10-31 Luis J. Garay

We present an analysis of scattering by a fluid-mechanical `black hole analogue', known as the draining bathtub vortex: a two-dimensional flow which possesses both a sonic horizon and an ergoregion. We consider the scattering of a plane…

General Relativity and Quantum Cosmology · Physics 2013-07-02 Sam R. Dolan , Ednilton S. Oliveira

A simple spacetime wormhole, which evolves classically from zero throat radius to a maximum value and recontracts, can be regarded as one possible mode of fluctuation in the microscopic ``spacetime foam'' first suggested by Wheeler. The…

General Relativity and Quantum Cosmology · Physics 2009-10-22 Ian Redmount , Wai-Mo Suen

We investigate the dissolution of artificial fractures with three-dimensional, pore-scale numerical simulations. The fluid velocity in the fracture space was determined from a lattice-Boltzmann method, and a stochastic solver was used for…

Geophysics · Physics 2015-05-13 P. Szymczak , A. J. C. Ladd

In certain extensions of General Relativity, wormholes generated by spherically symmetric electric fields can resolve black hole singularities without necessarily removing curvature divergences. This is shown by studying geodesic…

High Energy Physics - Theory · Physics 2016-04-20 Gonzalo J. Olmo , D. Rubiera-Garcia , A. Sanchez-Puente

Quantum-mechanical model of self-gravitating dust shell is considered. To clarify the relation between classical and quantum spacetime which the shell collapse form, we consider various time slicing on which quantum mechanics is developed.…

General Relativity and Quantum Cosmology · Physics 2011-09-09 K. Nakamura , Y. Oshiro , A. Tomimatsu

We research the entropy of a black hole in curved space-times by 't Hooft`s approach, so-called the brick wall method. One of these space-time, a asymptotically dS space-time has two physical horizons; one is a black hole horizon and the…

High Energy Physics - Theory · Physics 2007-05-23 Kyung-Seok Cha , Bum-Hoon Lee , Chanyong Park

On the quantum stage spacetime had the foam-like structure. When the Universe cools the foam structure temperes and therefore the Friedman model represents only the mean picture. We show that effects of the foamed structure we observe now…

Astrophysics · Physics 2007-05-23 A. A. Kirillov

We use ray-tracing techniques to determine the evolution of the event horizon of a large black hole that ``gobbles'' a tiny, traversable wormhole. This calculation has physical meaning in the extreme mass ratio limit. Two setups are…

General Relativity and Quantum Cosmology · Physics 2023-07-04 João M. Dias , Antonia M. Frassino , Valentin D. Paccoia , Jorge V. Rocha

The so-called ``brick-wall model'' is a semi-classical approach that has been used to explain black hole entropy in terms of thermal matter fields. Here, we apply the brick-wall formalism to thermal bulk fields in a Randall-Sundrum brane…

High Energy Physics - Theory · Physics 2009-11-07 A. J. M. Medved

In this work, we studied the boundary wormhole fluctuations of AdS$_{3}$ spacetime and their impact on false vacuum decay. The model consists of three dimensional general relativity coupled to a real scalar field with self-interaction…

High Energy Physics - Theory · Physics 2025-08-13 Hong Wang , Jin Wang

We compute the black hole entropy in the context of the Modified Dispersion Relations using the brick wall model. An explicit dependence of the radial coordinate approaching the horizon is shown to analyze the behavior of the divergence. We…

General Relativity and Quantum Cosmology · Physics 2010-03-02 Remo Garattini

A simple model of spacetime foam, made by N wormholes in a semiclassical approximation, is taken under examination. We show that the Bekenstein-Hawking entropy is here ``quantized'' in agreement with the heuristic calculation of Bekenstein.

High Energy Physics - Theory · Physics 2009-10-31 Remo Garattini

The first junction conditions of spherically symmetric bubbles are solved for some cases, and whereby analytic models to the Einstein field equations are constructed. The effects of bubbles on the spacetime structure are studied and it is…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Anzhong Wang , Patricio S. Letelier