English
Related papers

Related papers: Non-Riemannian model of the space-time responsible…

200 papers

There exist instances of dynamical systems possessing symmetry transformations of which the conserved Noether charges generating these symmetries feature an explicit time dependence in their functional representation over phase space. The…

High Energy Physics - Theory · Physics 2019-07-02 Jan Govaerts

The Einstein equations for an isotropic and homogeneous Friedmann--Robertson--Walker Universe in the presence of a quintessence scalar field are shown to be described in a unified way, formally identical to the dynamics of a relativistic…

General Relativity and Quantum Cosmology · Physics 2015-11-04 Sergio A. Hojman , Felipe A. Asenjo

The essential features of a quantum group deformation of classical symmetries of General Relativity in the case with non-vanishing cosmological constant $\Lambda$ are presented. We fully describe (anti-)de Sitter non-commutative spacetimes…

High Energy Physics - Theory · Physics 2020-03-10 Ivan Gutierrez-Sagredo , Angel Ballesteros , Giulia Gubitosi , Francisco J. Herranz

Flat cosmological models with a cosmological constant on the order of the Einstein-de Sitter critical density are enigmatic in the sense that there does not appear to be any natural explanation for why there should be a cosmological…

Astrophysics · Physics 2007-05-23 George Chapline

It is considered the model of the homogeneous and isotropic universe. The scale of length is defined via the laboratory scale of time by the motion of photon. This leads to the appearance of the inertial forces. The properties of the space…

Astrophysics · Physics 2007-05-23 D. L. Khokhlov

We develop a semiclassical framework for studying quantum particles constrained to curved surfaces using the momentous quantum mechanics formalism, which extends classical phase-space to include quantum fluctuation variables (moments). In a…

Quantum Physics · Physics 2026-01-29 Guillermo Chacon-Acosta , H. Hernandez-Hernandez , J. Ruvalcaba-Rascon

Semiclassical techniques have proven to be a very powerful method to extract physical effects from different quantum theories. Therefore, it is expected that in the near future they will play a very prominent role in the context of quantum…

General Relativity and Quantum Cosmology · Physics 2014-12-17 David Brizuela

A phenomenological model is proposed to explain the recent observed cosmological variation of the fine structure constant as an effect of the quantum vacuum, assuming a flat universe with cosmological constant $\Lambda$ in the cases…

Astrophysics · Physics 2010-12-17 Antonio F. Rañada

Quantum effects are expected to modify the cosmological dynamics of the early universe while maintaining some (potentially discrete) notion of space-time structure. In one approach, loop quantum cosmology, current models are shown here to…

General Relativity and Quantum Cosmology · Physics 2026-04-29 Martin Bojowald , Manuel Diaz , Erick I. Duque

Quantum field planes furnish a noncommutative differential algebra $\Omega$ which substitutes for the commutative algebra of functions and forms on a contractible manifold. The data required in their construction come from a quantum field…

High Energy Physics - Theory · Physics 2007-05-23 G. Mack , V. Schomerus

We study the potential effects of spacetime non-metricity in cosmology. In the spirit of Einstein-Cartan gravity, but with non-metricity replacing torsion, we consider the Einstein-Hilbert action and assume zero torsion. Adopting certain…

General Relativity and Quantum Cosmology · Physics 2023-03-29 Damianos Iosifidis , Ioannis Georgios Vogiatzis , Christos G. Tsagas

Astrophysical observations provide a picture of the universe as a 4-dim homogeneous and isotropic flat space-time dominated by an unknown form of dark energy. To achieve such a cosmology one has to consider in the early universe an…

Astrophysics · Physics 2009-11-10 F. Canfora , A. Troisi

A quantum Schwarzschild spacetime and a quantum Schwarzschild-de Sitter spacetime with cosmological constant $\Lambda$ are constructed within the framework of a noncommutative Riemannian geometry developed in an earlier publication. The…

High Energy Physics - Theory · Physics 2009-04-17 Ding Wang , R. B. Zhang , Xiao Zhang

There must exist a reformulation of quantum field theory which does not refer to classical time. We propose a pre-quantum, pre-spacetime theory, which is a matrix-valued Lagrangian dynamics for gravity, Yang-Mills fields, and fermions. The…

General Physics · Physics 2022-02-16 Tejinder P. Singh

A discrete class of privileged reference frames in a closed universe with identical equations of motion for physical degrees of freedom was found. A representation of the quantum state of the universe in a privileged reference frame was…

General Relativity and Quantum Cosmology · Physics 2025-12-17 Natalia Gorobey , Alexander Lukyanenk , A. V. Goltsev

Special relativity combined with the stochastic vacuum flux impact model lead to an explicit interpretation of many of the phenomena of elementary quantum mechanics. We examine characteristics of a repetitively impacted submicroscopic…

General Physics · Physics 2007-05-23 C. L. Herzenberg

We study special functions on euclidean spaces from the viewpoint of riemannian symmetric spaces. Here the euclidean space $E^n = G/K$ where $G$ is the semidirect product $R^n \cdot K$ of the translation group with a closed subgroup $K$ of…

Representation Theory · Mathematics 2007-05-23 Joseph A. Wolf

In a quantum cosmological model consisting of a Euclidean region and a Lorentzian region, Hartle-Hawking's no-bounary wave function, and Linde's wave function and Vilenkin's tunneling wave function are briefly described and compared with…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Sang Pyo Kim

Motivated by the search for a Hamiltonian formulation of Einstein equations of gravity which depends in a minimal way on choices of coordinates, nor on a choice of gauge, we develop a multisymplectic formulation on the total space of the…

Mathematical Physics · Physics 2017-01-30 Frédéric Hélein , Dimitri Vey

The formalism of classical and quantum mechanics on phase space leads to symplectic and Heisenberg group representations, respectively. The Wigner functions give a representation of the quantum system using classical variables. The…

Quantum Physics · Physics 2007-05-23 Ajay Patwardhan
‹ Prev 1 8 9 10 Next ›