English
Related papers

Related papers: The fallacies of LCDM falsifications

200 papers

Perhaps the deepest mystery of our accelerating Universe in expansion is the existence of a tiny and rigid cosmological constant, $\Lambda$. Its size is many orders of magnitude below the expected one in the standard model of particle…

General Relativity and Quantum Cosmology · Physics 2015-04-03 Joan Sola , Adria Gomez-Valent

The main foundations of the standard $\Lambda $CDM model of cosmology are that: 1) The redshifts of the galaxies are due to the expansion of the Universe plus peculiar motions; 2) The cosmic microwave background radiation and its…

Cosmology and Nongalactic Astrophysics · Physics 2017-03-08 Martin Lopez-Corredoira

Loop quantum cosmology is a conflicted field in which exuberant claims of observability coexist with serious objections against the conceptual and physical viability of its current formulations. This contribution presents a non-technical…

General Relativity and Quantum Cosmology · Physics 2021-06-28 Martin Bojowald

It has been claimed that the observed magnitude of the vacuum energy density is consistent with the distribution predicted in anthropic models, in which an ensemble of universes is assumed. This calculation is revisited, without making the…

Astrophysics · Physics 2009-06-23 J. A. Peacock

We examine the internal consistency of the Planck 2015 cosmic microwave background (CMB) temperature anisotropy power spectrum. We show that tension exists between cosmological constant cold dark matter (LCDM) model parameters inferred from…

Cosmology and Nongalactic Astrophysics · Physics 2016-02-24 G. E. Addison , Y. Huang , D. J. Watts , C. L. Bennett , M. Halpern , G. Hinshaw , J. L. Weiland

Different measurements of the Hubble constant ($H_{0}$) are not consistent and a tension between the CMB based methods and cosmic distance ladder based methods has been observed. Measurements from various distance based methods are also…

Cosmology and Nongalactic Astrophysics · Physics 2020-06-23 Rahul Kumar Thakur , Shashikant Gupta , Rahul Nigam , PK Thiruvikraman

In this paper we are exploring the differences between a Warm Dark Matter model and a CDM model where the power on a certain scale is reduced by introducing a narrow negative feature ("dip"). This dip is placed in a way so as to mimic the…

Astrophysics · Physics 2008-11-26 Brett Little , Alexander Knebe , Ranty Islam

The debate in cosmology concerning LambdaCDM and MOND depends crucially on their respective ability of modelling across scales, and dealing with some of the specific problems that arise along the way. The main upshot of this article is to…

Cosmology and Nongalactic Astrophysics · Physics 2018-11-26 Michela Massimi

We discuss a comparison of models for the formation of disk galaxies both in a Universe dominated by cold dark matter (CDM) and one in which the force law is given by modified Newtonian dynamics (MOND). Our main aim is to address the claim…

Astrophysics · Physics 2007-05-23 Frank C. van den Bosch , Julianne J. Dalcanton

Problems with the concordance cosmology $\Lambda$CDM as the cosmological constant problem, coincidence problems and Hubble tension has led to many proposed alternatives, as the $\Lambda(t)$CDM, where the now called $\Lambda$ cosmological…

Cosmology and Nongalactic Astrophysics · Physics 2026-02-03 H. A. P. Macedo , L. S. Brito , J. F. Jesus , M. E. S. Alves

The mixed cold-hot dark matter cosmological model (CHDM) with $\Omega_{tot}=1$ and a falling power-law initial spectrum of Gaussian adiabatic perturbations ($n>1$) is tested using recent obserbational data. It is shown that its fit to the…

Astrophysics · Physics 2009-10-22 Dmitri Pogosyan , Alexei Starobinsky

In the context of the new standard LambdaCDM cosmology we resolve conflicts in the literature regarding fundamental aspects of the expansion of the universe and cosmic horizons and we link these concepts to observational tests. We derive…

Astrophysics · Physics 2007-05-23 Tamara M. Davis

Anomalies in the cosmic microwave background (CMB) refer to features that have been observed, mostly at large angular scales, and which show some tension with the statistical predictions of the standard $\Lambda$CDM model. In this work, we…

General Relativity and Quantum Cosmology · Physics 2021-05-28 Ivan Agullo , Dimitrios Kranas , V. Sreenath

One of the most intriguing hints of a departure from the standard cosmological model is a large-scale dipolar power asymmetry in the cosmic microwave background (CMB). If not a statistical fluke, its origins must lie in the modulation of…

Cosmology and Nongalactic Astrophysics · Physics 2017-03-23 J. P. Zibin , D. Contreras

Current cosmological constraints on the scalar spectral index of primordial fluctuations $n_{\rm s}$ in the $\Lambda$CDM model have excluded the minimal scale-invariant Harrison-Zel'dovich model ($n_{\rm s}=1$; hereafter HZ) at high…

Cosmology and Nongalactic Astrophysics · Physics 2018-09-26 Eleonora Di Valentino , Alessandro Melchiorri , Yabebal Fantaye , Alan Heavens

A wide range of models describing modifications to General Relativity have been proposed, but no fundamental parameter set exists to describe them. Similarly, no fundamental theory exists for dark energy to parameterize its potential…

Cosmology and Nongalactic Astrophysics · Physics 2010-10-27 Viviana Acquaviva , Eric Gawiser

The measurements of the Hubble parameter using the cosmic microwave background radiation appear to be inconsistent with the measurements of this parameter using Cepheid variable stars. This inconsistency may be a result of using the…

General Physics · Physics 2021-01-25 Nikodem J. Popławski

Assuming a spatially flat universe, we study the cosmological viability of an infrared corrected teleparallel gravity model, which accounts for late acceleration by weakening gravity at later times on cosmological distances. The theory does…

Cosmology and Nongalactic Astrophysics · Physics 2023-01-11 Mahmoud Hashim , Waleed El Hanafy , Alexey Golovnev , Amr A. El-Zant

Modified gravity theories are a popular alternative to dark energy as a possible explanation for the observed accelerating cosmic expansion, and their cosmological tests are currently an active research field. Studies in recent years have…

Cosmology and Nongalactic Astrophysics · Physics 2016-10-12 Juan J. Ceron-Hurtado , Jian-hua He , Baojiu Li

I begin by briefly reviewing the evidence for the existence of Dark Matter (DM), emphasizing that {\em many} observations, at length scales between kpc (the size of the smallest galaxies) and Gpc (the Hubble radius) can be described by the…

High Energy Physics - Phenomenology · Physics 2018-11-16 Manuel Drees
‹ Prev 1 8 9 10 Next ›