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Related papers: Quantum Cosmology of Kantowski-Sachs like Models

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A consisten quantization with a clear notion of time and evolution is given for the anisotropic Kantowski-SDachs cosmological model. It is shown that a suitable coordinate choice allows to obtain a solution of the Wheeler-DeWitt equation in…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Claudio Simeone

One presents a phase-space noncommutative extension of Quantum Cosmology in the context of a Kantowski-Sachs (KS) minisuperspace model. We obtain the Wheeler-DeWitt (WDW) equation for the noncommutative system through the ADM formalism and…

High Energy Physics - Theory · Physics 2009-07-24 C. Bastos , O. Bertolami , N. Dias , J. Prata

We present a noncommutative extension of Quantum Cosmology and study the Kantowski-Sachs (KS) cosmological model requiring that the two scale factors of the KS metric, the coordinates of the system, and their conjugate canonical momenta do…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Catarina Bastos , Orfeu Bertolami , Nuno Costa Dias , João Nuno Prata

In this paper we study the quantum cosmological Kantowski-Sachs model and solve the Wheeler-DeWitt equation in minisuperspace to obtain the wave function of the corresponding universe. The perfect fluid is described by the Schutz's…

General Relativity and Quantum Cosmology · Physics 2016-11-11 F. G. Alvarenga , R. Fracalossi , R. C. Freitas , S. V. B. Gonçalves

We present a phase-space noncommutative version of quantum mechanics and apply this extension to Quantum Cosmology. We motivate this type of noncommutative algebra through the gravitational quantum well (GQW) where the noncommutativity…

High Energy Physics - Theory · Physics 2015-05-13 Catarina Bastos , Orfeu Bertolami , Nuno Dias , Joao Nuno Prata

Wheeler-DeWitt equation is applied to $k > 0$ Friedmann Robertson Walker metric with various types of matter. It is shown that if the Universe ends in the matter dominated era (e.g., radiation or pressureless gas) with zero cosmological…

High Energy Physics - Theory · Physics 2010-11-01 Jong Hyun Kung

In the present work, we study the noncommutative version of a quantum cosmology model. The model has a Friedmann-Robertson-Walker geometry, the matter content is a radiative perfect fluid and the spatial sections have positive constant…

General Relativity and Quantum Cosmology · Physics 2016-05-05 G. Oliveira-Neto , G. A. Monerat , E. V. Corrêa Silva , C. Neves , L. G. Ferreira Filho

Quantum cosmology is studied within the framework of the minimal quantum gravity theory proposed by Ho\v{r}ava. For this purpose we choose the Kantowski-Sachs (KS) model and construct the corresponding Wheeler-DeWitt equation. We study the…

General Relativity and Quantum Cosmology · Physics 2013-05-31 O. Obregón , J. A. Preciado

The Wheeler-DeWitt equation arising from a Kantowski-Sachs model is considered for a Schwarzschild black hole under the assumption that the scale factors and the associated momenta satisfy a noncanonical noncommutative extension of the…

High Energy Physics - Theory · Physics 2011-02-23 Catarina Bastos , Orfeu Bertolami , Nuno Costa Dias , João Nuno Prata

We use a path-integral approach to study the tunneling wave function in quantum cosmology with spatial topology $S^{1}\times S^{2}$ and positive cosmological constant (the Kantowski-Sachs model). If the initial scale factors of both $S^1$…

General Relativity and Quantum Cosmology · Physics 2022-09-07 Georgios Fanaras , Alexander Vilenkin

It is well-known that the standard WKB approximation fails to provide semiclassical solutions in the vicinity of turning points. However, turning points arise in many cosmological scenarios. In a previous work, we obtained a new class of…

General Relativity and Quantum Cosmology · Physics 2016-02-12 Antonin Coutant

In quantum cosmology, one has to select a specific wave function solution of the quantum state equations under consideration in order to obtain concrete results. The simplest choices have been already explored, in different frameworks,…

General Relativity and Quantum Cosmology · Physics 2021-09-06 P. C. M. Delgado , N. Pinto-Neto

We consider the conditioning of the timeless solution to the Wheeler-DeWitt equation by a predefined matter clock state in the simple scenario of de Sitter universe. The resulting evolution of the geometrodynamical degree of freedom with…

General Relativity and Quantum Cosmology · Physics 2019-02-26 Marcello Rotondo , Yasusada Nambu

We comment on two issues in quantum cosmology, in the context of the Wheeler-De Witt equation and wave function of the Universe: (i) arrow of time and interpretation of the wave function in the classically allowed regions; (ii) stability of…

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

First a Friedmann-Robertson-Walker (FRW) universe filled with dust and a conformally invariant scalar field is quantized. For the closed model we find a discrete set of wormhole quantum states. In the case of flat spacelike sections we find…

General Relativity and Quantum Cosmology · Physics 2015-06-25 Nivaldo A. Lemos , Flavio G. Alvarenga

In this paper we present a Friedmann-Robertson-Walker cosmological model conformally coupled to a massive scalar field where the WKB approximation fails to reproduce the exact solution to the Wheeler-DeWitt equation for large Universes. The…

General Relativity and Quantum Cosmology · Physics 2009-10-22 Esteban Calzetta , Juan Jose Gonzalez

We study the quantum cosmology of a quadratic $f(R)$ theory with a FRW metric, via one of its equivalent Horndeski type actions, where the dynamics of the scalar field is induced. The classical equations of motion and the Weeler-deWitt…

General Relativity and Quantum Cosmology · Physics 2017-06-22 V. Vázquez-Báez , C. Ramírez

We consider a cosmological model based upon a non-canonical noncommutative extension of the Heisenberg-Weyl algebra to address the thermodynamical stability and the singularity problem of both the Schwarzschild and the Kantowski-Sachs black…

High Energy Physics - Theory · Physics 2011-07-08 Catarina Bastos , Orfeu Bertolami , Nuno Costa Dias , João Nuno Prata

Bouncing models are alternatives to inflationary cosmology that replace the initial Big-Bang singularity by a `bouncing' phase. A deeper understanding of the initial conditions of the universe, in these scenarios, requires knowledge of…

General Relativity and Quantum Cosmology · Physics 2021-05-27 Karthik Rajeev , Vikramaditya Mondal , Sumanta Chakraborty

We propose a model for noncommutative quantum cosmology by means of a deformation of minisuperspace. For the Kantowski-Sachs metric we are able to find the exact wave function. We construct wave packets and show that new quantum states that…

High Energy Physics - Theory · Physics 2009-11-07 H. Garcia-Compean , O. Obregon , C. Ramirez
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