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Recently, some divergent conclusions about cosmic acceleration were obtained using type Ia supernovae (SNe Ia), with opposite assumptions on the intrinsic luminosity evolution. In this paper, we use strong gravitational lensing systems to…

Cosmology and Nongalactic Astrophysics · Physics 2019-02-20 Z. L. Tu , J. Hu , F. Y. Wang

Flat $\Lambda$CDM cosmology is specified by two constant fitting parameters at the background level in the late Universe, the Hubble constant $H_0$ and matter density (today) $\Omega_m$. Mathematically, $H_0$ and $\Omega_m$ are either…

Cosmology and Nongalactic Astrophysics · Physics 2024-03-19 Eoin Ó Colgáin , M. M. Sheikh-Jabbari , Rance Solomon , Maria G. Dainotti , Dejan Stojkovic

We test the theoretical predictions of several cosmological models against different observables to compare the indirect estimates of the current expansion rate of the Universe determined from model fitting with the direct measurements…

Cosmology and Nongalactic Astrophysics · Physics 2016-11-09 Vladimir V. Luković , Rocco D'Agostino , Nicola Vittorio

The best-fit values of the density parameter and the amplitude of the linear density power spectrum obtained from the Cosmic Microwave Background (CMB) temperature field scanned by the Planck satellite are found to notably disagree with…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-16 Jounghun Lee

The $\Lambda$CDM cosmolgical model has long been regarded as highly successful in accurately describing a wide range of astronomical observations. However, numerous observational findings have also provided hints of discrepancies from the…

Cosmology and Nongalactic Astrophysics · Physics 2025-12-01 Yupeng Yang

The Hubble diagram constructed using HII galaxies (HIIGx) and Giant extragalactic HII regions (GEHR) as standard candles already extends beyond the current reach of Type Ia SNe. A sample of 156 HIIGx and GEHR sources has been used…

Cosmology and Nongalactic Astrophysics · Physics 2018-09-20 Manoj K. Yennapureddy , Fulvio Melia

We re-analyze the Cepheid data used to infer the value of $H_0$ by calibrating SnIa. We do not enforce a universal value of the empirical Cepheid calibration parameters $R_W$ (Cepheid Wesenheit color-luminosity parameter) and $M_H^{W}$…

Cosmology and Nongalactic Astrophysics · Physics 2021-12-15 Leandros Perivolaropoulos , Foteini Skara

In this paper we compare data to theory. We use a compilation of the most recent cosmic microwave background (CMB) measurements to constrain Hubble's constant h, the baryon fraction Omega_b, and the cosmological constant lambda. We fit h-,…

Astrophysics · Physics 2008-02-03 Charles H. Lineweaver , Domingos Barbosa , Alain Blanchard , James G. Bartlett

In this paper, we test the cosmic distance duality (CDD) relation using the luminosity distances from joint light-curve analysis (JLA) type Ia supernovae (SNe Ia) sample and angular diameter distance sample from galaxy clusters. The…

Cosmology and Nongalactic Astrophysics · Physics 2018-05-02 J. Hu , F. Y. Wang

The set of cosmological density parameters ($\Omega_{0m}h_{0}^{2}$, $\Omega_{0k}h_{0}^{2}$, $\Omega_{0\Lambda}h_{0}^{2}$) and Hubble constant ($\hat{h}_{0}$) are useful for fundamental understanding of the universe from many perspectives.…

Cosmology and Nongalactic Astrophysics · Physics 2024-07-17 Srikanta Pal , Rajib Saha

Most dark energy models have the $\Lambda$CDM as their limit, and if future observations constrain our universe to be close to $\Lambda$CDM Bayesian arguments about the evidence and the fine-tuning will have to be employed to discriminate…

Cosmology and Nongalactic Astrophysics · Physics 2018-11-27 Olga Avsajanishvili , Yiwen Huang , Lado Samushia , Tina Kahniashvili

Recent re-calibration of the Type Ia supernova (SNe~Ia) magnitude-redshift relation combined with cosmic microwave background (CMB) and baryon acoustic oscillation (BAO) data have provided excellent constraints on the standard cosmological…

Cosmology and Nongalactic Astrophysics · Physics 2017-08-02 Suhail Dhawan , Ariel Goobar , Edvard Mörtsell , Rahman Amanullah , Ulrich Feindt

In this work, we present independent determinations of cosmological parameters and new constraints on $f(T)$ cosmologies, employing two new catalogs related to HII galaxy Hubble and CMB distance priors, along with the local standard…

Cosmology and Nongalactic Astrophysics · Physics 2024-05-13 Rodrigo Sandoval-Orozco , Celia Escamilla-Rivera , Rebecca Briffa , Jackson Levi Said

We present novel cosmological constraints based on a joint analysis of our HII galaxies (HIIG) Hubble relation with the full Planck Cosmic Microwave Background anisotropy spectrum and the Baryon Acoustic Oscillations (BAO) probes. The HII…

We use higher-redshift gamma-ray burst (GRB), HII starburst galaxy (HIIG), and quasar angular size (QSO-AS) measurements to constrain six spatially flat and non-flat cosmological models. These three sets of cosmological constraints are…

Cosmology and Nongalactic Astrophysics · Physics 2021-01-15 Shulei Cao , Joseph Ryan , Narayan Khadka , Bharat Ratra

The evolution of the Hubble parameter $H(z)$ with redshift $z$ is estimated from the Pantheon+ data of Type Ia supernovae, for the $\Lambda$CDM model and the three special cases of the eternal coasting (EC) cosmological model with three…

Cosmology and Nongalactic Astrophysics · Physics 2024-12-23 Ardra Edathandel Sasi , Moncy Vilavinal John

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

The standard relation between the cosmological redshift and cosmic scale factor underlies cosmological inference from virtually all kinds of cosmological observations, leading to the emergence of the LambdaCDM cosmological model. This…

Cosmology and Nongalactic Astrophysics · Physics 2019-08-08 Radosław Wojtak , Francisco Prada

We re-investigated the use of the Hubble diagram to measure the cosmological constant ($\Lambda$) and the mass density of the Universe ($\Omega_M$). We find an important focusing effect in $\Lambda$ for redshifts about 3. This effect…

Astrophysics · Physics 2009-10-31 Jorge Melnick , Roberto Terlevich , Elena Terlevich

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