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Related papers: Wormhole-generated physical universe

200 papers

We develop a new model for the Universe based on two key assumptions: first, the inertial energy of the Universe is a constant, and second, the total energy of a particle, the inertial plus the gravitational potential energy produced by the…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Hossein Shojaie , Mehrdad Farhoudi

Increasing improvements in the independent determinations of the Hubble constant and the age of the universe now seem to indicate that we need a small non-vanishing cosmological constant to make the two independent observations consistent…

High Energy Physics - Phenomenology · Physics 2009-10-28 Anupam Singh

In this paper, a general FRW cosmological model has been constructed in $f(R,T)$ gravity reconstruction with variable cosmological constant. A number of solutions to the field equations has been generated by utilizing a form for the Hubble…

General Relativity and Quantum Cosmology · Physics 2018-10-17 Nasr Ahmed , Sultan Z. Alamri

We study the classical and quantum Euclidean wormholes for an empty (4+1) dimensional Kaluza-Klein universe with a positive cosmological constant and a spatially flat Robertson-Walker type metric. It is shown that classical wormholes do not…

General Relativity and Quantum Cosmology · Physics 2015-05-30 F. Darabi

In a recent model Choudhury proposed that a collapsing matter generates an adiabatic pressure which can be used to explain the acceleration of the physical universe under certain approximation. In this work we superimpose the core pressure…

General Relativity and Quantum Cosmology · Physics 2008-05-26 A. M. Haruar Rashid , A. L. Choudhury

A simple and surprisingly realistic model of the origin of the universe can be developed using the Friedmann equation from general relativity, elementary quantum mechanics, and the experimental values of h, c, G and the proton mass. The…

General Relativity and Quantum Cosmology · Physics 2015-06-25 T. R. Mongan

In the Einstein-Cartan-Sciama-Kibble theory of gravity, the intrinsic spin of fermionic matter generates spacetime torsion and induces gravitational repulsion at extremely high densities. This repulsion prevents the collapsing spin-fluid…

General Relativity and Quantum Cosmology · Physics 2011-08-09 Nikodem J. Poplawski

We have considered a cosmological model with a cosmological constant of the form $\Lambda=3\alpha\frac{\dot R^2}{R^2}+\bt\frac{\ddot R}{R} \alpha, \bt=\rm const.$ The cosmological constant is found to decrease as $t^{-2}$ and the rate of…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Arbab I. Arbab

We show that in imaginary time quantum metric fluctuations of empty space form a self-consistent de Sitter gravitational instanton that can be thought of as describing tunneling from "nothing" into de Sitter space of real time (no…

General Relativity and Quantum Cosmology · Physics 2015-06-04 Leonid Marochnik

We present a complete quantum mechanical description of a flat FRW universe with equation of state p=\rho. We find a detailed correspondence with our heuristic picture of such a universe as a dense black hole fluid. Features of the geometry…

High Energy Physics - Theory · Physics 2009-11-10 T. Banks , W. Fischler , L. Mannelli

We point out that the standard formulation of the cosmological constant problem itself is problematic since it is trying to apply the very large scale homogeneous cosmological model to very small (Planck) scale phenomenon. At small scales,…

General Relativity and Quantum Cosmology · Physics 2020-08-05 Qingdi Wang , William G. Unruh

Combining intervals of ekpyrotic (ultra-slow) contraction with a (non-singular) classical bounce naturally leads to a novel cyclic theory of the universe in which the Hubble parameter, energy density and temperature oscillate periodically,…

General Relativity and Quantum Cosmology · Physics 2019-07-12 Anna Ijjas , Paul J. Steinhardt

We carry out to completion the quantization of a Friedmann-Robertson-Walker model provided with a conformal scalar field, and of a Kantowski-Sachs spacetime minimally coupled to a massless scalar field. We prove that the Hilbert space…

General Relativity and Quantum Cosmology · Physics 2010-11-01 Guillermo A Mena Marugan

In this work we present an analytical proof of cosmic censorship in a Kerr-like phantom wormhole (WH) which contains a singularity that is not protected by an event horizon. We show that the naked singularity of this space-time is causally…

General Relativity and Quantum Cosmology · Physics 2018-12-24 Juan Carlos Del Águila , Tonatiuh Matos

We have studied the evolution of the Universe in the generalized Einstein action of the form $R+\beta R^2$, where $R$ is the scalar curvature and $\beta=\rm const.$. We have found exact cosmological solutions that predict the present cosmic…

High Energy Physics - Theory · Physics 2008-11-21 Arbab I. Arbab

We generalize the fractal bubble model (FB), recently proposed in the literature as an alternative to the standard $\Lambda$CDM cosmology, to include a non-zero cosmological constant. We retain the same volume partition of voids and walls…

General Relativity and Quantum Cosmology · Physics 2012-01-30 Stefano Viaggiu

In 6D general relativity with a phantom scalar field as a source of gravity, we present solutions that implement a transition from an effective 4D geometry times small extra dimensions to an effectively 6D space-time where the physical laws…

General Relativity and Quantum Cosmology · Physics 2017-09-19 K. A. Bronnikov , P. A. Korolyov , A. Makhmudov , M. V. Skvortsova

We argue that one can nucleate a traversable wormhole via a nonperturbative process in quantum gravity. To support this, we construct spacetimes in which there are instantons giving a finite probability for a test cosmic string to break and…

High Energy Physics - Theory · Physics 2020-01-08 Gary T. Horowitz , Don Marolf , Jorge E. Santos , Diandian Wang

We show that in a two-dimensional model of quantum gravity the summation over all possible wormhole configurations leads to a kind of Coleman mechanism where the cosmological constant plays no role for large universes. Observers who are…

High Energy Physics - Theory · Physics 2021-02-24 Jan Ambjorn , Yuki Sato , Yoshiyuki Watabiki

The general world model for homogeneous and isotropic universe has been roposed. For this purpose, we introduce a global and fiducial system of reference (world reference frame) constructed on a 5-dimensional space-time that is embedding…

Astrophysics · Physics 2008-03-04 Chan-Gyung Park