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In this work, we develop and apply the WKB approximation to several examples of noncommutative quantum cosmology, obtaining the time evolution of the noncommutative universe, this is done starting from a noncommutative quantum formulation…

General Relativity and Quantum Cosmology · Physics 2009-03-24 E. Mena , O. Obregon , M. Sabido

We study noncommutative classical Friedmann-Robertson-Walker cosmological models. The constant curvature of the spatial sections can be positive ($k=1$), negative ($k=-1$) or zero ($k=0$). The matter is represented by a perfect fluid with…

General Relativity and Quantum Cosmology · Physics 2017-01-06 G. Oliveira-Neto , A. R. Vaz

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

This study investigates the cosmological dynamics of an accelerating universe within the framework of teleparallel gravity using an exponential f(T) functional form. To obtain exact cosmological solutions, a hybrid scale factor is employed…

General Relativity and Quantum Cosmology · Physics 2026-05-27 Rajalakshmi Jena , Vishal M C , Sankarsan Tarai

We study the cosmological aspects of a noncommutative, multidimensional universe where the matter source is assumed to be a scalar field which does not commute with the internal scale factor. We show that such noncommutativity results in…

General Relativity and Quantum Cosmology · Physics 2010-11-11 N. Khosravi , S. Jalalzadeh , H. R. Sepangi

Considering space--time to be non-commutative, we study the evolution of the universe employing the approach of Newtonian cosmology. Generalizing the conservation of energy and the first law of thermodynamics to $\kappa$-deformed…

General Relativity and Quantum Cosmology · Physics 2023-07-31 E. Harikumar , Harsha Sreekumar , Suman Kumar Panja

We consider multidimensional gravity with a Lagrangian containing the Ricci tensor squared and the Kretschmann invariant. In a Kaluza-Klein approach with a single compact extra space of arbitrary dimension, with the aid of a slow-change…

General Relativity and Quantum Cosmology · Physics 2009-11-13 K. A. Bronnikov , S. A. Kononogov , V. N. Melnikov , S. G. Rubin

We introduce the method and the implementation of a cosmological simulation of a class of metric-variation f(R) models that accelerate the cosmological expansion without a cosmological constant and evade solar-system bounds of small-field…

Astrophysics · Physics 2008-12-30 Hiroaki Oyaizu

In this talk we provide arguments on possible relation between the cosmological constant in our space and the non-commutativity parameter of the internal space of compactified string theory. The arguments are valid in the context of D3/D7…

High Energy Physics - Theory · Physics 2007-05-23 Renata Kallosh

In order to try explaining the present accelerated expansion of the universe, we consider the most complete noncommutativity, of a certain type, in a Friedmann-Robertson-Walker cosmological model, coupled to a perfect fluid. We use the ADM…

General Relativity and Quantum Cosmology · Physics 2021-06-23 G. Oliveira-Neto , L. Fazza Marcon

In this study, we explore the pre-inflationary dynamics of the universe using a noncommutative extension of the mLQC-I framework. By incorporating a scalar field potential, we show that key features of Loop Quantum Cosmology (LQC), such as…

General Relativity and Quantum Cosmology · Physics 2024-08-13 Abolhassan Mohammadi

We present a novel formulation for the Hubble parameter derived from Newtonian cosmology, incorporating non-commutative fluid dynamics through a deformed Poisson bracket structure. This approach introduces a new cosmological parameter,…

General Relativity and Quantum Cosmology · Physics 2026-02-13 Raj Kumar Das , Arpan Krishna Mitra

We investigate the possible occurrence of a positive cosmic acceleration in a spatially averaged, expanding, unbound Lemaitre-Tolman-Bondi cosmology. By studying an approximation in which the contribution of three-curvature dominates over…

Astrophysics · Physics 2009-11-11 Aseem Paranjape , T. P. Singh

We consider astrophysical objects such as main-sequence stars, white-dwarfs and neutron stars in a noncommutative context. Noncommutativity is implemented via a deformed dispersion relation $E^{2}=p^{2}c^{2}(1+\lambda E)^{2}+m^{2}c^{4}$…

General Relativity and Quantum Cosmology · Physics 2013-05-29 Orfeu Bertolami , Carlos A. D. Zarro

We consider the noncommutative minisuperspace classical and quantum cosmologies.

High Energy Physics - Theory · Physics 2007-08-30 Aleksandar Zejak , Branko Dragovich

In this paper, we present an accelerating cosmological model by constraining the free parameters using the cosmological datasets in an extended symmetric teleparallel gravity for the flat and anisotropic space-time. We employ a time…

General Relativity and Quantum Cosmology · Physics 2023-06-27 S. A. Narawade , M. Koussour , B. Mishra

We present a parallel between commutative and non-commutative polymorphisms. Our emphasis is the applications to conditional distributions from stochastic processes. In the classical case, both the measures and the positive definite kernels…

Quantum Physics · Physics 2025-01-22 Palle E. T. Jorgensen , James Tian

Since microscopic velocity diffusion can be incorporated into general relativity in a consistent way, we study cosmological background solutions when the diffusion phenomena takes place in an expanding universe. Our focus here relies on the…

Cosmology and Nongalactic Astrophysics · Physics 2016-05-10 Hermano Velten , Simone Calogero

We address the question how to adapt cosmological constant $\Lambda$ for description of a vacuum dark energy density jumping from the big initial value to the small today value suggested by observations. We find such a possibility in the…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Irina Dymnikova , Michael Fil'chenkov

Two examples of the situation when the classical observables should be described by a noncommutative probability space are investigated. Possible experimental approach to find quantum-like correlations for classical disordered systems is…

Quantum Physics · Physics 2009-11-07 Andrei Khrennikov , Sergei Kozyrev