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Related papers: Thermodynamics of noncommutative de Sitter spaceti…

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Taking quantum physics as well as large scale astronomical observations into account, a spacetime metric is introduced, such that the nonlinear part of the Einstein tensor contains effects of the order of Planck's constant.

General Relativity and Quantum Cosmology · Physics 2015-06-25 J. Lamey , G. M. Obermair

In this work, we investigate the thermodynamics of Schwarzschild black and white holes within a $q$-deformed Wheeler--DeWitt framework. By introducing a $q$-deformed Heisenberg--Weyl algebra at a root of unity, we derive a…

General Relativity and Quantum Cosmology · Physics 2026-03-31 S. Jalalzadeh , R. Jalalzadeh , H. Moradpour

We argue that the minimal length discretization generalizing the Heisenberg uncertainty principle, in which the gravitational impacts on the non--commutation relations are thoughtfully taken into account, radically modifies the spacetime…

General Physics · Physics 2021-12-01 Abdel Nasser Tawfik , Fady T. Farouk , F. Salah Tarabia , Muhammad Maher

We study some consequences of noncommutativity to homogeneous cosmologies by introducing a deformation of the commutation relation between the minisuperspace variables. The investigation is carried out for the Kantowski-Sachs model by means…

High Energy Physics - Theory · Physics 2009-11-10 G. D. Barbosa , N. Pinto-Neto

The dynamics of a particle in a gravitational quantum well is studied in the context of nonrelativistic quantum mechanics with a particular deformation of a two-dimensional Heisenberg algebra. This deformation yields a new short-distance…

High Energy Physics - Theory · Physics 2008-11-26 F. Brau , F. Buisseret

In terms of the Beltrami model of de Sitter space we show that there is an interchangeable relation between Snyder's quantized space-time model in dS-space of momenta at the Planck length $\ell_P=(G\hbar c^{-3})^{1/2}$ and the dS-invariant…

High Energy Physics - Theory · Physics 2007-05-23 Han-Ying Guo

In a suitably chosen essentially unique frame tied to a given observer in a general spacetime, the equation of geodesic deviation can be decomposed into a sum of terms describing specific effects: isotropic (background) motions associated…

General Relativity and Quantum Cosmology · Physics 2009-10-31 J. Bicak , J. Podolsky

We investigate consequences of allowing the Hilbert space of a quantum system to have a time-dependent metric. For a given possibly nonstationary quantum system, we show that the requirement of having a unitary Schreodinger time-evolution…

Quantum Physics · Physics 2015-06-26 Ali Mostafazadeh

In this thesis we study different aspects of noncommutativity in quantum mechanics, field theory and gravity. We give particular emphasis on the underlying symmetries of these theories. Deformations of usual symmetries like the external…

High Energy Physics - Theory · Physics 2010-06-08 Saurav Samanta

In this paper, we derive corrections to the geodesic equation due to the $k$-deformation of curved space-time, up to the first order in the deformation parameter a. This is done by generalizing the method from our previous paper [31], to…

High Energy Physics - Theory · Physics 2013-12-16 E. Harikumar , T. Juric , S. Meljanac

Black holes have been a subject of investigation over years not only because they have interesting physical properties, but also because they seem to be the appropriate tool for studying gravity in quantum scale. Although a lot of effort…

General Relativity and Quantum Cosmology · Physics 2020-12-09 Joao Chakrian , Antonio de Padua Santos

In this paper we study a new symmetry argument that results in a vacuum state with strictly vanishing vacuum energy. This argument exploits the well-known feature that de Sitter and Anti- de Sitter space are related by analytic…

General Relativity and Quantum Cosmology · Physics 2009-11-11 Gerard 't Hooft , Stefan Nobbenhuis

We derive non-flat cosmological models for two cases (i.e., dust and radiation) in the context of M{\o}ller's tetradic theory (MTT) of gravitation using the tetrad that creates the non-flat Friedmann-Robertson-Walker (FRW) metric. These two…

General Relativity and Quantum Cosmology · Physics 2022-04-21 G. G. L. Nashed , A. T. Shafeek

With the basic cosmological relations that agree with the recent observations, simple expressions are suggested concerning the value of cosmological constant($\Lambda$). A large contribution of quantum vacuum to the energy momentum tensor…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Ishwaree P. Neupane

In this paper, we investigate the influence of spatial curvature on the Jaynes-Cummings model. We employ an analog model of general relativity, representing the field inside a cavity using oscillators arranged in a circle instead of a…

Quantum Physics · Physics 2025-07-09 Somayeh Kourkinejat , Ali Mahdifar , Ehsan Amooghorban

Well tempering is one of the few classical field theory methods for solving the original cosmological constant problem, dynamically canceling a large (possibly Planck scale) vacuum energy and leaving the matter component intact, while…

Cosmology and Nongalactic Astrophysics · Physics 2021-01-15 Stephen Appleby , Eric V. Linder

We discuss the difference between the thermodynamics of black holes and thermodynamics of the de Sitter expansion. Both systems experience the Hawking radiation, but its impact on thermodynamics is different. As distinct from the…

General Relativity and Quantum Cosmology · Physics 2026-04-07 G. E. Volovik

An extensively tacit understandings of equivalency between the deformed Heisenberg-Weyl algebra in noncommutative space and the undeformed Heisenberg-Weyl algebra in commutative space is elucidated. Equivalency conditions between two…

Quantum Physics · Physics 2007-05-23 Jian-Zu Zhang

It is well known that nonrelativistic quantum mechanics presents a clear asymmetry between space and time. Much of this asymmetry is attributed to the lack of Lorentz invariance of the theory. Nonetheless, a recent work [Phys. Rev. A…

Quantum Physics · Physics 2017-12-12 Ricardo Ximenes , Eduardo O. Dias

The event horizon is a source of irreversibility, analogous to statistical irreversibility. This is why for systems with an event horizon there is no difference between quantum and thermal fluctuations. Quantum processes of quantum…

General Relativity and Quantum Cosmology · Physics 2025-10-16 G. E. Volovik
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