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Related papers: Revisiting Fractional Cosmology

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In this work we present a brief discussion about modified and extended cosmological models using current observational tests. We show that according to these astrophysical samples based in late universe measurements, theories like $f(R)$…

General Relativity and Quantum Cosmology · Physics 2021-01-25 Celia Escamilla-Rivera

We consider perturbative modifications of the Friedmann equations in terms of energy density corresponding to modified theories of gravity proposed as an alternative route to comply with the observed accelerated expansion of the universe.…

General Relativity and Quantum Cosmology · Physics 2015-05-13 L. Fernández-Jambrina , R. Lazkoz

We introduce an ingenious approach to explore cosmological implications of higher-derivative gravity theories. The key novelty lies in the characterization of the additional massive spin-0 modes constructed from Hubble derivatives as an…

General Relativity and Quantum Cosmology · Physics 2025-12-16 H. Khodabakhshi , M. Farhang , F. Shojai , H. Lü

Methods from the geometry of nonholonomic manifolds and Lagrange-Finsler spaces are applied in fractional calculus with Caputo derivatives and for elaborating models of fractional gravity and fractional Lagrange mechanics. The geometric…

Mathematical Physics · Physics 2011-06-03 Dumitru Baleanu , Sergiu I. Vacaru

A new approach for arbitrary dimension to the Friedmann cosmological models is presented. Taking suitable changes of the parameters of the spacetime the harmonic motion equations appear, where the curvature determines the angular frequency.…

General Relativity and Quantum Cosmology · Physics 2014-03-03 Rafael M. Rubio , Juan J. Salamanca

We are witnessing the birth of a new variety of pharmacokinetics where non-integer-order differential equations are employed to study the time course of drugs in the body: this is dubbed "fractional pharmacokinetics." The presence of…

Dynamical Systems · Mathematics 2019-04-25 Pantelis Sopasakis , Haralambos Sarimveis , Panos Macheras , Aristides Dokoumetzidis

The method of four-dimensional Causal Dynamical Triangulations provides a background-independent definition of the sum over geometries in quantum gravity, in the presence of a positive cosmological constant. We present the evidence…

High Energy Physics - Theory · Physics 2007-05-23 J. Ambjorn , J. Jurkiewicz , R. Loll

We consider $f(R)$ modified gravity theory incorporating the chameleon mechanism to address galactic dynamics. By employing the metric formalism and utilizing a conformal transformation, we simplify the field equations and describe the…

General Relativity and Quantum Cosmology · Physics 2024-09-04 Gayatri Mohan , Umananda Dev Goswami

For fractional derivatives and time-fractional differential equations, we construct a framework on the basis of the operator theory in fractional Sobolev spaces. Our framework provides a feasible extension of the classical Caputo and the…

Analysis of PDEs · Mathematics 2022-01-24 Masahiro Yamamoto

In this paper we present a number of examples of exact solutions for the Friedmann cosmological equation for metric $ F(R) $ gravity model. Emphasis was placed on the possibility of obtaining exact time dependences of the main cosmological…

General Relativity and Quantum Cosmology · Physics 2024-01-31 Maria Shubina

We study the effective cosmological dynamics, emerging as the hydrodynamics of simple condensate states, of a group field theory model for quantum gravity coupled to a massless scalar field and reduced to its isotropic sector. The quantum…

General Relativity and Quantum Cosmology · Physics 2016-11-23 Daniele Oriti , Lorenzo Sindoni , Edward Wilson-Ewing

There are many resources useful for processing images, most of them freely available and quite friendly to use. In spite of this abundance of tools, a study of the processing methods is still worthy of efforts. Here, we want to discuss the…

Computer Vision and Pattern Recognition · Computer Science 2015-04-08 Amelia Carolina Sparavigna

Fractional differential equations model processes with memory effects, providing a realistic perspective on complex systems. We examine time-delayed differential equations, discussing first-order and fractional Caputo time-delayed…

General Relativity and Quantum Cosmology · Physics 2025-05-08 Bayron Micolta-Riascos , Byron Droguett , Gisel Mattar Marriaga , Genly Leon , Andronikos Paliathanasis , Luis del Campo , Yoelsy Leyva

In the realm of complexity, it is argued that adequate modeling of TeV-physics demands an approach based on fractal operators and fractional calculus (FC). Non-local theories and memory effects are connected to complexity and the FC. The…

High Energy Physics - Theory · Physics 2013-06-25 Cresus F. L. Godinho , J. Weberszpil , J. A. Helayël-Neto

This work proposes a conformable fractional predictor-corrector algorithm for solving conformable fractional differential equations. Fractional calculus is finding applications in various scientific fields, but existing numerical methods…

Numerical Analysis · Mathematics 2024-06-25 Mohamed Echchehira , Youness Assebbane , Mustapha Atraoui , Mohamed Bouaouid

We construct the higher order terms of curvatures in Lagrangians of the scale factor for the Friedmann-Lemaitre-Robertson-Walker universe, which are linear in the second derivative of the scale factor with respect to cosmic time. It is…

General Relativity and Quantum Cosmology · Physics 2013-04-02 Nahomi Kan , Koichiro Kobayashi , Kiyoshi Shiraishi

This paper presents a better approach to model an engineering problem in fractal-time space based on local fractional calculus. Some examples are given to elucidate to establish governing equations with local fractional derivative.

Mathematical Physics · Physics 2011-10-31 Xiao-Jun Yang

This study investigates the possibility of a homogeneous and isotropic cosmological solution within the context of the Maxwell-Weyl gauge theory of gravity. To achieve this, we utilize the Einstein-Yang-Mills theory as an analogy and…

General Relativity and Quantum Cosmology · Physics 2024-07-26 Salih Kibaroğlu

In Chapter 1 I present the current picture of the universe and briefly review the cosmological constant problem and some of the theories proposed to solve it. The following Chapters essentially contain the published papers with some…

General Relativity and Quantum Cosmology · Physics 2014-08-10 Lorenzo Reverberi

Friedmans cosmological equations for the scale factor are analyzed for the Universe containing dark energy. The parameter of the equation of state of the dark energy is treated as an arbitrary constant whose value lies within the interval…

Cosmology and Nongalactic Astrophysics · Physics 2011-09-13 M. V. Sazhin , O. S. Sazhina , U. Chadayammuri
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