English
Related papers

Related papers: Model Comparison of $\Lambda$CDM vs $R_h=ct$ using…

200 papers

The recently constructed Hubble diagram using a combined sample of SNLS and SDSS-II Type Ia SNe, and an application of the Alcock-Paczynski (AP) test using model-independent Baryon Acoustic Oscillation data, have suggested that the…

Cosmology and Nongalactic Astrophysics · Physics 2018-09-25 Fulvio Melia , Thomas M. McClintock

We present a novel approach to test the consistency of the cosmological models with multiband CMB data using a nonparametric approach. In our analysis we calibrate the REACT (Risk Estimation and Adaptation after Coordinate Transformation)…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-15 Amir Aghamousa , Arman Shafieloo

We continue to build support for the proposal to use HII galaxies (HIIGx) and giant extragalactic HII regions (GEHR) as standard candles to construct the Hubble diagram at redshifts beyond the current reach of Type Ia supernovae. Using a…

Cosmology and Nongalactic Astrophysics · Physics 2016-08-24 Jun-Jie Wei , Xue-Feng Wu , Fulvio Melia

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

The use of Type~Ia SNe has thus far produced the most reliable measurement of the expansion history of the Universe, suggesting that $\Lambda$CDM offers the best explanation for the redshift--luminosity distribution observed in these…

Cosmology and Nongalactic Astrophysics · Physics 2018-06-22 Jun-Jie Wei , Xue-Feng Wu , Fulvio Melia , Robert S. Maier

In this study, we present an analysis of the standard flat-$\Lambda$CDM model using a cosmographic approach, incorporating recent DESI BAO observations and Supernovae Type Ia catalogues (SNIa), including the DES-SN5YR and Pantheon+…

Cosmology and Nongalactic Astrophysics · Physics 2025-01-28 Saeed Pourojaghi , Mohammad Malekjani , Zahra Davari

Using a fully Bayesian approach, Gaussian Process regression is extended to include marginalisation over the kernel choice and kernel hyperparameters. In addition, Bayesian model comparison via the evidence enables direct kernel comparison.…

Cosmology and Nongalactic Astrophysics · Physics 2024-02-13 Namu Kroupa , David Yallup , Will Handley , Michael Hobson

The DESI collaboration just obtained a set of precise BAO measurements, that combined with CMB and SNIa datasets show that the $\omega_0 \omega_a$CDM model is preferred over $\Lambda$CDM, at more than $4\,\sigma$, to describe the dynamics…

Cosmology and Nongalactic Astrophysics · Physics 2025-07-02 Fernanda Oliveira , Felipe Avila , Camila Franco , Armando Bernui

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

Under the assumption of a flat Lambda-CDM cosmology, recent data from the Planck satellite point toward a Hubble constant that is in tension with that measured by gravitational lens time delays and by the local distance ladder. Prosaically,…

Gaussian processes offers a convenient way to perform nonparametric reconstructions of observational data assuming only a kernel which describes the covariance between neighbouring points in a data set. We approach the ambiguity in the…

Cosmology and Nongalactic Astrophysics · Physics 2021-08-17 Reginald Christian Bernardo , Jackson Levi Said

Despite the ability of the cosmological concordance model ($\Lambda$CDM) to describe the cosmological observations exceedingly well, power law expansion of the Universe scale radius, $R(t)\propto t^n$, has been proposed as an alternative…

We use 32 age measurements of passively evolving galaxies as a function of redshift to test and compare the standard model ($\Lambda$CDM) with the $R_{\rm h}=ct$ Universe. We show that the latter fits the data with a reduced $\chi^2_{\rm…

Cosmology and Nongalactic Astrophysics · Physics 2015-07-15 Jun-Jie Wei , Xue-Feng Wu , Fulvio Melia , Fa-Yin Wang , Hai Yu

In this paper I investigate how well simple power law expansion fits observational data in comparison to the standard $\Lambda$CDM model. I analyze a data set consisting of cosmic chronometer, standard ruler, and standard candle…

Cosmology and Nongalactic Astrophysics · Physics 2021-08-25 Joseph Ryan

This paper studies both $\Lambda$CDM and CDM models under the \"uber gravity theory, named \"u$\Lambda$CDM and \"uCDM respectively. We report bounds over their parameter phase-space using several cosmological data, in particular, the recent…

Cosmology and Nongalactic Astrophysics · Physics 2023-05-10 Gustavo A. Concha Valdez , Claudia Quintanilla , Miguel A. García-Aspeitia , A. Hernández-Almada , V. Motta

The tension between measurements of the Hubble constant $H_0$ locally and the value inferred from Planck satellite have provided a strong motivation to explore theoretical frameworks beyond the standard cosmological model ($\Lambda$CDM). To…

General Relativity and Quantum Cosmology · Physics 2025-08-29 R. Mohebi , Kh. Saaidi T. Golanbari , K. Karami

The backbone of standard cosmology is the Friedmann-Robertson-Walker solution to Einstein's equations of general relativity (GR). In recent years, observations have largely confirmed many of the properties of this model, which is based on a…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 Fulvio Melia , Andrew Shevchuk

A natural extension of the standard cosmological model are models that include curvature as a free parameter. In this work we study in detail the observational constraints on the non-flat $\Lambda CDM$ model using the two main geometric…

Cosmology and Nongalactic Astrophysics · Physics 2020-01-15 Velasquez-Toribio , A. M , Magnago , A. dos R

Whereas many measurements in cosmology depend on the use of integrated distances or time, galaxies evolving passively on a time scale much longer than their age difference allow us to determine the expansion rate H(z) solely as a function…

Cosmology and Nongalactic Astrophysics · Physics 2018-09-21 Jun-Jie Wei , Fulvio Melia , Xue-Feng Wu

We have investigated the constraints on the Cardassian model using the recent results from the Wilkinson Microwave Anisotropy Probe (WMAP) for the locations of the peaks of the Cosmic Microwave Background (CMB) anistropy spectrum. We find…

Astrophysics · Physics 2016-08-30 A. A. Sen , S. Sen