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Our proposed cosmological framework, which is based on fractional quantum cosmology, aims to address the issue of synchronicity in the age of the universe. To achieve this, we have developed a new fractional $\Lambda$CDM cosmological model.…

Based on Padmanabhan's theory, the spatial expansion of the Universe can be explained by the emergence of space as cosmic time progresses. To further explore this idea, we have developed fractional-fractal Friedmann and Raychaudhuri…

General Relativity and Quantum Cosmology · Physics 2023-09-29 P. F. da Silva Junior , E. W. de Oliveira Costa , S. Jalalzadeh

The age of the universe is obtained in a subset of Cardassian models by using WMAP data. Cardassian expansion is a modification to the Friedmann equation that allows the universe to be flat, matter dominated, and accelerating, without a…

Astrophysics · Physics 2016-08-30 Christopher Savage , Noriyuki Sugiyama , Katherine Freese

Assuming that observers located inside the Universe measure a time flow which is different from the time appearing in the Friedmann-Lemaitre equation, and determining this time flow such that the Universe always appears flat to these…

Cosmology and Nongalactic Astrophysics · Physics 2012-12-24 Pierre Magain

We investigate the thermodynamical properties of the apparent horizon in a fractal universe. We find that one can always rewrite the Friedmann equation of the fractal universe in the form of the entropy balance relation $ \delta Q=T_h…

General Physics · Physics 2015-06-12 Ahmad Sheykhi , Zeinab Teimoori , Bin Wang

Fractional cosmology modifies the standard derivative to Caputo's fractional derivative of order $\mu$, generating changes in General Relativity. Friedmann equations are modified, and the evolution of the species densities depends on $\mu$…

General Relativity and Quantum Cosmology · Physics 2022-10-26 Miguel A. García-Aspeitia , Guillermo Fernandez-Anaya , A. Hernández-Almada , Genly Leon , Juan Magaña

We apply the property of selfsimilarity that corresponds to the concept of a fractal universe, to the dimension of time. It follows that any interval of time, given by any tick of any clock, is proportional to the age of the universe. The…

General Physics · Physics 2009-05-26 Antonio Alfonso-Faus

It was shown by Tsallis and Cirto that thermodynamical entropy of a gravitational system such as black hole must be generalized to the non-additive entropy, which is given by $S_h=\gamma A^{\beta}$, where $A$ is the horizon area and $\beta$…

General Relativity and Quantum Cosmology · Physics 2018-09-26 Ahmad Sheykhi

We disclose the thermodynamical properties of the apparent horizon in a nonsingular universe. We take into account the zero-point length correction to the gravitational potential and derive the modified entropy expression that includes…

General Relativity and Quantum Cosmology · Physics 2025-05-06 Ahmad Sheykhi , Leila Liravi , Kimet Jusufi

The fractal cosmological model which accounts for observable fractal properties of the Universe's large-scale structure is constructed. In this framework these properties are consequences of the rotary symmetry of charged scalar meson…

Cosmology and Nongalactic Astrophysics · Physics 2012-12-03 I. K. Rozgacheva , A. A. Agapov

Starting from the first law of thermodynamics, $dE=T_hdS_h+WdV$, at apparent horizon of a FRW universe, and assuming that the associated entropy with apparent horizon has a quantum corrected relation, $S=\frac{A}{4G}-\alpha \ln…

High Energy Physics - Theory · Physics 2011-02-09 Ahmad Sheykhi

As the universe expands astronomical observables such as brightness and angular size on the sky change in ways that differ from our simple Cartesian expectation. We show how observed quantities depend on the expansion of space and…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 Jodi Christiansen , Andy Siver

We present a brief history of the construction of models of the universe, followed by calculations of quantitative characteristics of basic geometric and kinematic properties of the Standard Cosmological Model ($\Lambda$CDM). Using the…

General Relativity and Quantum Cosmology · Physics 2026-04-23 D. I. Nagirner , S. G. Jorstad , A. V. Dementyev

Based on the mathematical similarity between the Friedman open metric and Godel's metric in the case of nearby distances, we investigate a new scenario for the Universe's evolution, where the present Friedman universe originates from a…

General Relativity and Quantum Cosmology · Physics 2009-10-31 Saulo Carneiro

The clustering of galaxies is well characterized by fractal properties, with the presence of an eventual cross-over to homogeneity still a matter of considerable debate. In this letter we discuss the cosmological implications of a fractal…

Astrophysics · Physics 2009-10-31 M. Joyce , P. W. Anderson , M. Montuori , L. Pietronero , F. Sylos Labini

Assuming a fractal distribution of matter in the universe, consequences that follow from the General Theory of Relativity and the Copernican Principle for fractal cosmology are examined. The change in perspective necessary to deal with a…

Astrophysics · Physics 2007-05-23 A. K. Mittal , Daksh Lohiya

In `entropic cosmology', instead of a cosmological constant $\Lambda$, an extra driving term is added to the Friedmann equation and the acceleration equation, taking into account the entropy and the temperature on the horizon of the…

Cosmology and Nongalactic Astrophysics · Physics 2013-03-14 Nobuyoshi Komatsu , Shigeo Kimura

Estimates of the fractal dimension $D$ of the set of galaxies in the universe, based on ever improving data sets, tend to settle on $D\approx 2$. This result raised a raging debate due to its glaring contradiction with astrophysical models…

The general relativistic cosmological Friedmann equations which describe how the scale factor of the universe evolves are expanded explicitly to include energy forms not usually seen. The evolution of the universe as predicted by the…

Astrophysics · Physics 2008-11-26 Robert J. Nemiroff , Bijunath Patla

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
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