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Related papers: Bayesian correction of $H(z)$ data uncertainties

200 papers

Aiming at exploring the nature of dark energy (DE), we use forty-three observational Hubble parameter data (OHD) in the redshift range $0 < z \leqslant 2.36$ to make a cosmological model-independent test of the $\Lambda$CDM model with…

Cosmology and Nongalactic Astrophysics · Physics 2021-07-13 Shu-Lei Cao , Xiao-Wei Duan , Xiao-Lei Meng , Tong-Jie Zhang

We present a cosmographic study designed to test the simplest type of accelerating cosmology: a flat universe with matter and a cosmological constant ($\Lambda$). Hubble series expansions are fit to the SCP Union2.1 supernova data set to…

Cosmology and Nongalactic Astrophysics · Physics 2015-11-17 Brett Bochner , Damon Pappas , Menglu Dong

$Om(z)$ is a diagnostic approach to distinguish dark energy models. However, there are few articles to discuss what is the distinguishing criterion. In this paper, firstly we smooth the latest observational $H(z)$ data using a…

General Relativity and Quantum Cosmology · Physics 2016-06-13 Jing-Zhao Qi , Ming-Jian Zhang , Wen-Biao Liu

In this paper, we propose a new parametrization of $Om(z)$ diagnostics and show how the most recent and significantly improved observations concerning the $H(z)$ and SN Ia measurements can be used to probe the consistency or tension between…

Cosmology and Nongalactic Astrophysics · Physics 2018-06-13 Jing-Zhao Qi , Shuo Cao , Marek Biesiada , Tengpeng Xu , Yan Wu , Sixuan Zhang , Zong-Hong Zhu

We use simulated Hubble parameter data in the redshift range 0 \leq z \leq 2 to explore the role and power of observational H(z) data in constraining cosmological parameters of the {\Lambda}CDM model. The error model of the simulated data…

Cosmology and Nongalactic Astrophysics · Physics 2011-03-11 Cong Ma , Tong-Jie Zhang

Scientific machine learning increasingly uses spectral methods to understand physical systems. Current spectral learning approaches provide only point estimates without uncertainty quantification, limiting their use in safety-critical…

Machine Learning · Computer Science 2025-09-17 Mohammad Nooraiepour

Computer models are commonly used to represent a wide range of real systems, but they often involve some unknown parameters. Estimating the parameters by collecting physical data becomes essential in many scientific fields, ranging from…

Applications · Statistics 2020-05-27 Chih-Li Sung , Beau David Barber , Berkley J. Walker

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

We re-analyse recent Cepheid data to estimate the Hubble parameter $H_0$ by using Bayesian hyper-parameters (HPs). We consider the two data sets from Riess et al 2011 and 2016 (labelled R11 and R16, with R11 containing less than half the…

Cosmology and Nongalactic Astrophysics · Physics 2017-03-30 Wilmar Cardona , Martin Kunz , Valeria Pettorino

We discuss the cosmological degeneracy between the Hubble parameter H(z), the age of the universe and cosmological parameters describing simple variations from the minimal LCDM model. We show that independent determinations of the Hubble…

Astrophysics · Physics 2014-11-18 Daniel G. Figueroa , Licia Verde , Raul Jimenez

We use 28 Hubble parameter, $H(z)$, measurements at intermediate redshifts $0.07 \leq z \leq 2.3$ to determine the present-day Hubble constant $H_0$ in four cosmological models. We measure $H_0 = 68.3^{ +2.7}_{ -2.6 }, 68.4^{ +2.9 }_{ -3.3…

Cosmology and Nongalactic Astrophysics · Physics 2017-01-26 Yun Chen , Suresh Kumar , Bharat Ratra

We use Bayesian model selection techniques to test extensions of the standard flat LambdaCDM paradigm. Dark-energy and curvature scenarios, and primordial perturbation models are considered. To that end, we calculate the Bayesian evidence…

Direct measurements of Hubble parameters $H(z)$ are very useful for cosmological model parameters inference. Based on them, Sahni, Shafieloo and Starobinski introduced a two-point diagnostic $Omh^2(z_i, z_j)$ as an interesting tool for…

Cosmology and Nongalactic Astrophysics · Physics 2018-08-24 Xiaogang Zheng , Marek Biesiada , Xuheng Ding , Shuo Cao , Sixuan Zhang , Zong-Hong Zhu

Uncertainty quantification is a central challenge in reliable and trustworthy machine learning. Naive measures such as last-layer scores are well-known to yield overconfident estimates in the context of overparametrized neural networks.…

Machine Learning · Computer Science 2023-05-24 Lucas Clarté , Bruno Loureiro , Florent Krzakala , Lenka Zdeborová

Using 137,562 quasars in the redshift range $2.1\leq z\leq3.5$ from the Data Release 11 (DR11) of the Baryon Oscillation Spectroscopic Survey (BOSS) of Sloan Digital Sky Survey (SDSS)-III, the BOSS-SDSS collaboration estimated the expansion…

General Relativity and Quantum Cosmology · Physics 2015-12-02 Suresh Kumar

We examine the validity of the $\Lambda$CDM model, and probe for the dynamics of dark energy using latest astronomical observations. Using the $Om(z)$ diagnosis, we find that different kinds of observational data are in tension within the…

Cosmology and Nongalactic Astrophysics · Physics 2017-06-14 Yuecheng Zhang , Hanyu Zhang , Dandan Wang , Yanghan Qi , Yuting Wang , Gong-Bo Zhao

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

The strong discrepancy between local and inverse distance ladder estimates of the Hubble constant $H_0$ could be pointing towards new physics beyond $\Lambda$CDM. Several attempts to address this tension through new physics rely on extended…

Cosmology and Nongalactic Astrophysics · Physics 2020-07-15 Sunny Vagnozzi

Clinical decision-making demands uncertainty quantification that provides both distribution-free coverage guarantees and risk-adaptive precision, requirements that existing methods fail to jointly satisfy. We present a hybrid…

Machine Learning · Computer Science 2026-01-06 Marzieh Amiri Shahbazi , Ali Baheri , Nasibeh Azadeh-Fard

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