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Related papers: Space Time Foam: a ground state candidate for Quan…

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In this paper, we investigate the role of gravito-inertial effects on the Casimir energy of a massless scalar field confined between two parallel plates orbiting a static and zero tidal Schwarzschild-like wormhole, at zero temperature.…

General Relativity and Quantum Cosmology · Physics 2021-03-02 A. C. L. Santos , C. R. Muniz , L. T. Oliveira

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

Spacetime undergoes quantum fluctuations, giving rise to spacetime foam, a.k.a. quantum foam. We discuss some properties of spacetime foam, and point out the conceptual interconnections in the physics of quantum foam, black holes, and…

General Relativity and Quantum Cosmology · Physics 2009-11-10 Y. Jack Ng

I propose a phenomenological description of space-time foam and discuss the experimental limits that are within reach of forthcoming experiments.

General Relativity and Quantum Cosmology · Physics 2014-11-17 Giovanni Amelino-Camelia

This thesis investigates traversable wormhole spacetimes in modified theories of gravity, where the matter at the wormhole throat is described by an anisotropic energy-momentum tensor. Wormhole solutions are constructed in the context of…

General Relativity and Quantum Cosmology · Physics 2025-04-15 Zinnat Hassan

In this letter, we investigate the changes in the quantum vacuum energy density of a massless scalar field inside a Casimir cavity that orbits a wormhole, by considering the cosmological model with an isotropic form of the Morris-Thorne…

General Relativity and Quantum Cosmology · Physics 2024-09-05 A. C. L. Santos , C. R. Muniz , L. T. Oliveira

Due to quantum fluctuations, spacetime is foamy on small scales. The degree of foaminess is found to be consistent with the holographic principle. One way to detect spacetime foam is to look for halos in the images of distant quasars.…

General Relativity and Quantum Cosmology · Physics 2009-05-01 Y. Jack Ng

In order to gain insight into the possible Ground State of Quantized Einstein's Gravity, we have derived a variational calculation of the energy of the quantum gravitational field in an open space, as measured by an asymptotic observer…

General Relativity and Quantum Cosmology · Physics 2015-06-25 G. Preparata , R. Rovelli , S. -S. Xue

Due to quantum fluctuations, spacetime is probably ``foamy'' on very small scales. We propose to detect this texture of spacetime foam by looking for core-halo structures in the images of distant quasars. We find that the Very Large…

General Relativity and Quantum Cosmology · Physics 2009-11-11 W. A. Christiansen , Y. Jack Ng , H. van Dam

Hawking's spacetime foam model predicts that due to quantum fluctuations, spacetime is filled with black hole like objects. We argue that Hawking's model implies a cosmological constant of the observed order and that it can also be used to…

General Relativity and Quantum Cosmology · Physics 2018-10-24 Benjamin Schulz

Following the subtraction procedure for manifolds with boundaries, we calculate by variational methods, the Schwarzschild-de Sitter and the de Sitter space energy difference. By computing the one loop approximation for TT tensors we…

General Relativity and Quantum Cosmology · Physics 2009-10-31 Remo Garattini

We show from one-loop quantum gravity and statistical thermodynamics that the thermodynamics of quantum foam in flat space-time and Schwarzschild space-time is exactly the same as that of Hawking-Unruh radiation in thermal equilibrium. This…

General Relativity and Quantum Cosmology · Physics 2016-08-31 Liao Liu , Yongge Ma

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

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

An approximate model of a spacetime foam is presented. It is supposed that in the spacetime foam each quantum handle is like to an electric dipole and therefore the spacetime foam is similar to a dielectric. If we neglect of linear sizes of…

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

In recent years there has been a growing interest in the field of Casimir wormhole. In classical general relativity (GR), it is known that the null energy condition (NEC) has to be violated to have a wormhole to be stable. The Casimir…

General Relativity and Quantum Cosmology · Physics 2022-12-13 Zinnat Hassan , Sayantan Ghosh , P. K. Sahoo , Kazuharu Bamba

Spacetime foam can be modeled in terms of nonlocal effective interactions in a classical nonfluctuating background. Then, the density matrix for the low-energy fields evolves, in the weak-coupling approximation, according to a master…

General Relativity and Quantum Cosmology · Physics 2016-08-25 Luis J. Garay

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

Casimir energy is always indicated as a potential source to generate a Traversable Wormhole. It is also used to proof the existence of negative energy which can be built in the laboratory. However, in the scientific literature there is no…

General Relativity and Quantum Cosmology · Physics 2020-01-08 Remo Garattini

The space-time foam formulas, quoted below in Eqs (1) and (3), express the minimal amount of quantum uncertainty to be introduced into the structure of the Einsteinian space-time in order to make that structure compatible with quantum…

Quantum Physics · Physics 2010-11-09 Andor Frenkel