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Related papers: $R_h=ct$ and the eternal coasting cosmological mod…

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Based on dramatic observations of the CMB with WMAP and of Type Ia supernovae with the Hubble Space Telescope and ground-based facilities, it is now generally believed that the Universe's expansion is accelerating. Within the context of…

Astrophysics · Physics 2007-11-30 Fulvio Melia

We present a rich class of exact solutions which contains radiation-dominated and matter-dominated models for the early and late universe. They include a variable cosmological ``constant'' which is derived from a higher dimension and…

General Relativity and Quantum Cosmology · Physics 2014-11-17 Hongya Liu , Paul S. Wesson

In arXiv:1601.02203, a simple model has been proposed in order to solve one of the problems related with the cosmological constant. The model is given by a topological field theory and the model has an infinite numbers of the BRS…

High Energy Physics - Theory · Physics 2017-07-19 Taisaku Mori , Daisuke Nitta , Shin'ichi Nojiri

In this thesis, the implications of a new cosmological model are studied, which has features similar to that of decaying vacuum cosmologies. Decaying vacuum (or cosmological constant \Lambda) models are the results of attempts to resolve…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Moncy V. John

We propose a cosmological model in which the universe undergoes an endless sequence of cosmic epochs each beginning with a `bang' and ending in a `crunch.' The temperature and density are finite at each transition from crunch to bang.…

High Energy Physics - Theory · Physics 2009-11-07 Paul J. Steinhardt , Neil Turok

A strictly linear evolution of the cosmological scale factor is surprisingly an excellent fit to a host of cosmological observations. Any model that can support such a coasting presents itself as a falsifiable model as far as classical…

Astrophysics · Physics 2007-05-23 Savita Gehlaut , Pranav Kumar , Geetanjali , Daksh Lohiya

The $R_h = ct$ cosmological model has received considerable attention in recent years owing to claims that it is favoured over the standard $\Lambda$ cold dark matter ($\Lambda$CDM) model by most observational data. A key feature of the…

Cosmology and Nongalactic Astrophysics · Physics 2016-05-04 Do Young Kim , Anthony N. Lasenby , Michael P. Hobson

Self-similar, spherically symmetric cosmological models with a perfect fluid and a scalar field with an exponential potential are investigated. New variables are defined which lead to a compact state space, and dynamical systems methods are…

General Relativity and Quantum Cosmology · Physics 2010-11-19 Alan Coley , Martin Goliath

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

In recent years, some studies have drawn attention to the lack of large-angle correlations in the observed cosmic microwave background (CMB) temperature anisotropies with respect to that predicted within the standard $\Lambda$CDM model.…

Cosmology and Nongalactic Astrophysics · Physics 2016-11-23 Gabriel R. Bengochea , Gabriel Leon

In [1], KKLT give a mechanism to generate de Sitter vacua in string theory. And the scenario, \emph{Landscape}, is suggested to explain the problem of the cosmological constant. In this paper, adopting a simple potential describing the…

High Energy Physics - Theory · Physics 2007-05-23 Cheng-Yi Sun , De-Hai Zhang

In a recent paper (Vigoureux et al. Int. J. Theor. Phys. 47:928, 2007) it has been suggested that the velocity of light and the expansion of the universe are two aspects of one single concept connecting space and time in the expanding…

Cosmology and Nongalactic Astrophysics · Physics 2011-03-22 David Viennot , Jean-Marie Vigoureux

This paper investigates the phenomenon of emergence of spatial curvature. This phenomenon is absent in the Standard Cosmological Model, which has a flat and fixed spatial curvature (small perturbations are considered in the Standard…

Cosmology and Nongalactic Astrophysics · Physics 2017-09-01 Krzysztof Bolejko

The horizon problem in the standard model of cosmology (LDCM) arises from the observed uniformity of the cosmic microwave background radiation, which has the same temperature everywhere (except for tiny, stochastic fluctuations), even in…

Cosmology and Nongalactic Astrophysics · Physics 2018-09-26 Fulvio Melia

A phenomenological model with an extreme accuracy is proposed for the cosmic time variation of the primordial fundamental constants (e, h, G and c) and the leptonic masses. The model is purely exploratory in that at the very early times the…

General Physics · Physics 2008-01-15 Dara Faroughy

Primordial nucleosynthesis is rightly hailed as one of the great successes of the standard cosmological model. Here we consider the initial forging of elements in the recently proposed Rh = ct universe, a cosmology that demands linear…

Cosmology and Nongalactic Astrophysics · Physics 2016-05-25 Geraint F. Lewis , Luke A. Barnes , Rajesh Kaushik

We focus on the class of cosmological models with a time-evolving vacuum energy density of the form $\rho_\Lambda=C_0+C_1 H+C_2 H^2$, where $H$ is the Hubble rate. Higher powers of $H$ could be important for the early inflationary epoch,…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-13 Adria Gomez-Valent , Joan Sola

It is well-known that quantum field theory (QFT) induces a huge value of the cosmological constant, $\Lambda$, which is outrageously inconsistent with cosmological observations. We review here some aspects of this fundamental theoretical…

General Relativity and Quantum Cosmology · Physics 2022-07-19 Joan Sola Peracaula

Current astronomical observations are successfully explained by the present cosmological paradigm based on the concordance model ($\Lambda_0$CDM + Inflation). However, such a scenario is composed of a heterogeneous mix of ingredients for…

General Relativity and Quantum Cosmology · Physics 2018-08-29 J. A. S Lima , Douglas Singleton

A recent analysis of the Supernova Ia data claims a 'marginal' ($\sim3\sigma$) evidence for a cosmic acceleration. This result has been complemented with a non-accelerating $R_{h}=ct$ cosmology, which was presented as a valid alternative to…

Cosmology and Nongalactic Astrophysics · Physics 2017-03-22 Balakrishna S. Haridasu , Vladimir V. Luković , Rocco D'Agostino , Nicola Vittorio