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Related papers: The fractal cosmological model

200 papers

We investigate the possibility of replacing the cosmological constant with gradual condensation of a scalar field produced during the decay of a superheavy dark matter. The advantage of this class of models to the ordinary quintessence is…

Astrophysics · Physics 2009-11-10 Houri Ziaeepour

Scalar-tensor gravitational theories are important extensions of standard general relativity, which can explain both the initial inflationary evolution, as well as the late accelerating expansion of the Universe. In the present paper we…

General Relativity and Quantum Cosmology · Physics 2017-06-28 J. A. Belinchón , T. Harko , M. K. Mak

The standard cosmological model assumes a homogeneous and isotropic universe as the background spacetime on large scales called the cosmological principle. However, some observations suggest the possibility of an inhomogeneous and…

Cosmology and Nongalactic Astrophysics · Physics 2022-07-08 Koki Yamashita , Yue Nan , Yuuki Sugiyama , Kazuhiro Yamamoto

We consider implications of the microscopic dynamics of spacetime for the evolution of cosmological models. We argue that quantum geometry effects may lead to stochastic fluctuations of the gravitational constant, which is thus considered…

General Relativity and Quantum Cosmology · Physics 2022-09-15 Marco de Cesare , Fedele Lizzi , Mairi Sakellariadou

We construct a family of measures for random fields based on the iterated subdivision of simple geometric shapes (triangles, squares, tetrahedrons) into a finite number of similar shapes. The intent is to construct continuum limits of scale…

High Energy Physics - Theory · Physics 2012-07-05 Arnab Kar , S. G. Rajeev

A scalar field with an exponential potential has the particular property that it is attracted into a solution in which its energy scales as the dominant component (radiation or matter) of the Universe, contributing a fixed fraction of the…

Astrophysics · Physics 2007-05-23 Pedro G. Ferreira

The distribution of visible matter in the universe, such as galaxies and galaxy clusters, has its origin in the week fluctuations of density that existed at the epoch of recombination. The hierarchical distribution of the universe, with its…

Cosmology and Nongalactic Astrophysics · Physics 2015-01-21 Bruce N. Miller , Jean-Louis Rouet , Yui Shiozawa

A closed mathematical model of the statistical self-gravitating system of scalar charged particles for conformal invariant scalar interactions is constructed on the basis of relativistic kinetics and gravitation theory. Asymptotic…

General Relativity and Quantum Cosmology · Physics 2015-08-13 Yurii Ignat'ev

We study static configurations of dark matter coupled to a scalar field responsible for the dark energy of the Universe. The dark matter is modelled as a Fermi gas within the Thomas-Fermi approximation. The mass of the dark matter particles…

Astrophysics · Physics 2009-11-13 N. Brouzakis , N. Tetradis

The question of the nature of galaxy clustering and the possible homogeneity of galaxy distribution is one of the fundamental problem of cosmology. It is well established that galaxy structures are characterized, up to a certain scale, by…

Astrophysics · Physics 2007-05-23 Francesco Sylos Labini , Luciano Pietronero

In this contribution, we investigate hierarchical nature of large-scale structure clustering through the oscillatory nature of the solutions of the Schr\"{o}dinger-like Friedmann equation in a modified gravitational background described by…

General Relativity and Quantum Cosmology · Physics 2022-10-05 Heba Sami , Amare Abebe

One of the fundamental challenges for quantum cosmology is to explain the emergence of our macroscopic Universe from physics at the Planck scale. In the group field theory (GFT) approach to quantum gravity, such a macroscopic universe…

General Relativity and Quantum Cosmology · Physics 2019-02-12 Steffen Gielen

This thesis tackles the vast question of generating accelerated periods of expansion of the universe. Models loosely related were developed in the early and late universe. In the early universe, generalizations of the Schwinger effect were…

General Relativity and Quantum Cosmology · Physics 2017-02-21 Clément Stahl

The universe is found to have undergone several phases in which the gravitational constant had different behaviors. During some epochs the energy density of the universe remained constant and the universe remained static. In the radiation…

Astrophysics · Physics 2007-05-23 Arbab I. Arbab

We have fossil evidence from the thermal background radiation that our universe expanded from a considerably hotter denser state. We have a well defined and testable description of the expansion, the relativistic Friedmann-Lemaitre model.…

Astrophysics · Physics 2009-10-31 P. J. E. Peebles

We examine Friedmann-Robertson-Walker models in three spacetime dimensions. The matter content of the models is composed of a perfect fluid, with a $\gamma$-law equation of state, and a homogeneous scalar field minimally coupled to gravity…

General Relativity and Quantum Cosmology · Physics 2009-10-31 Norman Cruz , Cristian Martinez

Scaling properties of Yang-Mills fields are used to show that fractal structures are expected to be present in system described by those theories. We show that the fractal structure leads to recurrence formulas that allow the determination…

High Energy Physics - Theory · Physics 2019-05-17 Airton Deppman , Eugenio Megias , Debora Perez Menezes

In a recent paper, a cosmological model based on El Naschie {\it E} infinity cantorian spacetime was presented [Iovane, G.; Chaos, Solitons and Fractals, 20: 657-667, (2004)]. In that work it was claimed that the present accelerated…

Astrophysics · Physics 2007-05-23 Eduardo Sergio Santini , Guillermo Andrés Lemarchand

It has been argued that the small perturbations to the homogeneous and isotropic configurations of a canonical scalar field in an expanding universe do not grow. We show that this is not true in general, and clarify the root of the…

General Relativity and Quantum Cosmology · Physics 2015-09-23 Miguel Alcubierre , Axel de la Macorra , Alberto Diez-Tejedor , José M. Torres

The current understanding of structure formation in the early universe is mainly built on a magnification of quantum fluctuations in an initial vacuum state during an early phase of accelerated universe expansion. One usually describes this…

Astrophysics · Physics 2008-08-06 Martin Bojowald , Aureliano Skirzewski