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Related papers: Cosmography of Cardassian model

200 papers

We consider approaches to cosmological parameter estimation in the inflationary cosmology, focussing on the required accuracy of the initial power spectra. Parametrizing the spectra, for example by power-laws, is well suited to testing the…

Astrophysics · Physics 2009-11-07 Samuel M. Leach , Andrew R. Liddle , Jerome Martin , Dominik J. Schwarz

The cosmological principle states that the Universe is statistically homogeneous and isotropic at large distance scales. There currently exist many observations which indicate a departure from this principle. It has been shown that many of…

Cosmology and Nongalactic Astrophysics · Physics 2023-03-31 Shamik Ghosh , Pankaj Jain , Rahul Kothari , Mohit Panwar , Gurmeet Singh , Prabhakar Tiwari

Asteroseismology has the capability of delivering stellar properties which would otherwise be inaccessible, such as radii, masses and thus ages of stars. When coupling this information with classical determinations of stellar parameters,…

Solar and Stellar Astrophysics · Physics 2015-06-22 Luca Casagrande

A non-trivial spatial topology of the Universe is a potentially observable attribute, which can be probed through the circles-in-the-sky for all locally homogeneous and isotropic universes with no assumptions on the cosmological parameters.…

Cosmology and Nongalactic Astrophysics · Physics 2009-04-21 M. J. Reboucas

The complexity and accuracy of current and future precision cosmology observational campaigns has made it essential to develop an efficient technique for directly combining simulation and observational datasets to determine cosmological and…

Astrophysics · Physics 2009-11-11 Katrin Heitmann , David Higdon , Charles Nakhleh , Salman Habib

The timescape cosmology represents a potentially viable alternative to the standard homogeneous cosmology, without the need for dark energy. Although average cosmic evolution in the timescape scenario only differs substantially from that of…

Cosmology and Nongalactic Astrophysics · Physics 2013-08-12 James A. G. Duley , M. Ahsan Nazer , David L. Wiltshire

Cosmography is a model-independent phenomenological approach to observational cosmology, relying on Taylor series expansions of physical quantities as a function of the cosmological redshift or other analogous variables. A recent work…

Cosmology and Nongalactic Astrophysics · Physics 2025-08-27 C. J. A. P. Martins

We present a strategy for a statistically rigorous Bayesian approach to the problem of determining cosmological parameters from the results of observations of anisotropies in the cosmic microwave radiation background. We propose the…

Astrophysics · Physics 2007-05-23 Nelson Christensen , Renate Meyer

We have a well-established standard model for cosmology and prospects for considerable additions from work in progress. I offer a list of elements of the standard model, comments on controversies in the interpretation of the evidence in…

Astrophysics · Physics 2007-05-23 P. J. E. Peebles

Usually, we assume that there is no inhomogeneity isotropic in terms of our location in our uni- verse. This assumption has not been observationally confirmed yet in sufficient accuracy, and we need to consider the possibility that there…

Cosmology and Nongalactic Astrophysics · Physics 2017-03-06 Hiroyuki Negishi , Ken-ichi Nakao

In quantum cosmology, one applies quantum physics to the whole universe. While no unique version and no completely well-defined theory is available yet, the framework gives rise to interesting conceptual, mathematical and physical…

General Relativity and Quantum Cosmology · Physics 2015-01-21 Martin Bojowald

Being based on the only assumption that the universe is homogenous and isotropic on large scales, cosmography is an ideal tool to investigate the cosmic expansion history in a almost model-independent way. Fitting the data on the luminosity…

Cosmology and Nongalactic Astrophysics · Physics 2011-11-10 S. Capozziello , V. F. Cardone , H. Farajollahi , A. Ravanpak

A comparison of the standard models in particle physics and in cosmology demonstrates that they are not compatible, though both are well established. Basics of modern cosmology are briefly reviewed. It is argued that the measurements of the…

High Energy Physics - Phenomenology · Physics 2008-11-26 A. D. Dolgov

We study a uniform and isotropic cosmology with a decaying vacuum energy density, in the realm of a model with a time varying gravitational "constant". We show that, for late times, such a cosmology is in accordance with the observed values…

General Relativity and Quantum Cosmology · Physics 2016-11-09 Saulo Carneiro

Investigating the accelerated expansion of the universe with cosmography is a best method to constraint cosmological models. In this work, in the $F(G)$ modified gravity framework, we obtain equations of motion in a flat FRW metric. Then we…

General Physics · Physics 2012-06-04 M. R. Setare , N. Mohammadipour

In recent years, there have been increasing challenges to the cosmological principle, based on new observations of e.g. supernovae and the cosmic bulk flow. As a result, the cosmological community is speaking their concern for the…

General Relativity and Quantum Cosmology · Physics 2026-05-15 Robbert W. Scholtens , Marcello Seri , Holger Waalkens , Rien van de Weygaert

A mathematical model of the Universe evolution, based on asymmetric doublet of classical and phantom dcalar Higgs fields with a kinetic connection between the components, has been constructed and studied. A detailed qualitative analysis was…

General Relativity and Quantum Cosmology · Physics 2024-11-26 Yu. G. Ignat'ev , I. A. Kokh

The Cosmological Principle (CP) -- the notion that the Universe is spatially isotropic and homogeneous on large scales -- underlies a century of progress in cosmology. It is conventionally formulated through the…

Presented cosmological model is 3D brane world sheet moved in extra dimension with variable scale factor. Analysis of the geodesic motion of the test particle gives settle explanation of the Pioneer effect. It is found that for considered…

General Relativity and Quantum Cosmology · Physics 2007-05-23 W. B. Belayev

The holographic principle sets an upper bound on the total entropy content of the Universe. Within the limits of a Newtonian approximation, a quantum-mechanical model is presented to describe the cosmological fluid. Under the assumption…

General Relativity and Quantum Cosmology · Physics 2023-07-19 P. Fernandez de Cordoba , J. M. Isidro