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We propose the new quantization of homogenous cosmological models. Four fundamental methods are applied to the cosmological model and efficiently jointed. The Dirac method for constrained systems is used, then the Fock space is built and…

General Relativity and Quantum Cosmology · Physics 2009-11-22 L. A. Glinka

We study a closed model of the universe filled with viscous fluid and quintessence matter components in a Brans-Dicke type cosmological model. The dynamical equations imply that the universe may look like an accelerated flat…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Francisco Pena , Mauricio Cataldo , Sergio del Campo

At large scales and for sufficiently early times, dark matter is described as a pressureless perfect fluid---dust---non-interacting with Standard Model fields. These features are captured by a simple model with two scalars: a Lagrange…

Cosmology and Nongalactic Astrophysics · Physics 2015-04-30 Fabio Capela , Sabir Ramazanov

The universe is viewed as a dust gas filling a sphere and floating in infinite empty space. Einstein's gravitational equations are applied to this case together with appropriate boundary values. The equations are solved for initial…

General Relativity and Quantum Cosmology · Physics 2015-12-01 Ingo Müller , Wolf Weiss

The origin of dark matter in galactic halos, one of the deepest unsolved problems in astrophysics, may find an unexpected contribution from the quantum mechanics of ordinary atomic hydrogen. We show that quantum entanglement and coherence…

Astrophysics of Galaxies · Physics 2026-05-12 Martin Houde , Fereshteh Rajabi , Lamies Sati , Vahid Anari

In this work we propose the quantization of a cosmological model describing the primordial universe filled with five barotropic fluids, namely: radiation, dust, vacuum, cosmic strings and domain walls. We intend to identify which fluid is…

General Relativity and Quantum Cosmology · Physics 2019-12-04 G. A. Monerat , C. G. M. Santos , F. G. Alvarenga , S. V. B. Gonçalves , R. Fracalossi , E. V. Corrêa Silva , G. Oliveira-Neto

Recently, a model of modified gravity plus single scalar field model was proposed, in which the scalar couples both to the standard Riemannian volume form given by the square root of the determinant of the Riemannian metric, as well as to…

General Relativity and Quantum Cosmology · Physics 2016-12-09 Denitsa Staicova , Michail Stoilov

We perform a reduced phase space quantization of gravity using four Klein-Gordon scalar fields as reference matter as an alternative to the Brown-Kuchar dust model in [1], where dust scalar fields are used. We compare our results to an…

General Relativity and Quantum Cosmology · Physics 2022-12-05 Kristina Giesel , Almut Vetter

We propose gravity, matters and dark energy may be confined on different four dimensional \emph{minimal surfaces} for the observer in five dimensional spacetime. Following this idea, we construct the equations of motion when gravity,…

General Relativity and Quantum Cosmology · Physics 2019-10-30 Changjun Gao , Shuang Yu

A relativistic equation is proposed for the bound state of two particles, which is in accord with the boundary condition for the propagation of the negative-energy states and reduces to the (one-body)Dirac equation in the infinite limit of…

High Energy Physics - Phenomenology · Physics 2008-02-03 Hitoshi Ito

In this research, we investigate the quantum and classical phase transitions of the Dirac particles in a homogeneously magnetized curved rotating 2+1 dimensional spacetime. We consider the intricate relationship between geometry and quantum…

General Relativity and Quantum Cosmology · Physics 2024-09-30 Nusret Sahan , Erdem Sucu

In this paper within the scope of FRW cosmology for k = 0, \pm1 we study the dynamics of the universe for a cosmological model with a scalar field nonminimally coupled to matter. By best- fitting the model parameters with the observational…

General Relativity and Quantum Cosmology · Physics 2012-07-09 H. Farajollahi , A. Salehi

A weak version of the cosmic censorship hypothesis is implemented as a set of boundary conditions on exact semi-classical solutions of two-dimensional dilaton gravity. These boundary conditions reflect low-energy matter from the strong…

High Energy Physics - Theory · Physics 2009-10-07 J. Russo , L. Susskind , L. Thorlacius

In generic curved spacetimes, the unavailability of a natural choice of vacuum state introduces a serious ambiguity in the Fock quantization of fields. In this review, we study the case of fermions described by a Dirac field in several…

General Relativity and Quantum Cosmology · Physics 2021-06-02 Jerónimo Cortez , Beatriz Elizaga Navascués , Guillermo A. Mena Marugán , Santiago Prado , José M. Velhinho

A fractional quantization in a two dimensional space is proposed. The angular momenta of the two dimensional electrons are quantized in fractional numbers by the boundary conditions on a multi-layered Riemann surface. Extended wave…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 Hyeong Rag Lee

In this paper we analyze the Dark Matter problem and the distribution of matter through two different approaches, which are linked by the possibility that the solution of these astronomical puzzles should be sought in the quantum imprinting…

General Relativity and Quantum Cosmology · Physics 2019-05-08 I. Licata , G. Iovane , L. Chiatti , E. Benedetto , F. Tamburini

Classical objects have been excluded as subjects of the observed quantum properties, and the related problem of quantum objects nature has been suspended since the early days of Quantum Theory. Recent experiments show that the problem could…

Quantum Physics · Physics 2021-08-06 Artur Szczepanski

A cosmological time variable is emerged from the Hamiltonian formulation of Friedmann model to measure the evolution of dynamical observables in the theory. A set of observables has been identified for the theory on the null hypersurfaces…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Hossein Farajollahi

The classical and quantum dynamics of the Friedmann-Robertson-Walker Universe with massless scalar and massive fermion matter field as a source is discussed in the framework of the Dirac generalized Hamiltonian formalism. The Hamiltonian…

General Relativity and Quantum Cosmology · Physics 2009-11-07 A. M. Khvedelidze , Yu. G. Palii

It is proposed that space is a four-dimensional Euclidean space with universal time. Originally this space was filled with a uniform substance, pictured as a liquid, which at some time became supercooled. Our universe began as a nucleation…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Michael Grady