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相关论文: Bayesian correction of $H(z)$ data uncertainties

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It is well known that estimating cosmological parameters from cosmic microwave background (CMB) data alone results in a significant degeneracy between the total neutrino mass and several other cosmological parameters, especially the Hubble…

宇宙学与河外天体物理 · 物理学 2018-03-28 Will Sutherland

We present a systematic comparison of statistical approaches to Baryon Acoustic Oscillation (BAO) analysis using DESI DR2 data. We evaluate four methods for handling the nuisance parameter $\beta=1/(H_0 r_d)$: marginalization, profiling,…

宇宙学与河外天体物理 · 物理学 2026-03-19 Denitsa Staicova

High fidelity radio interferometric data calibration that minimises spurious spectral structure in the calibrated data is essential in astrophysical applications, such as 21 cm cosmology, which rely on knowledge of the relative spectral…

天体物理仪器与方法 · 物理学 2022-10-26 Peter H. Sims , Jonathan C. Pober , Jonathan L. Sievers

Ideally, a meta-analysis will summarize data from several unbiased studies. Here we consider the less than ideal situation in which contributing studies may be compromised by measurement error. Measurement error affects every study design,…

In this article, we employ a machine learning (ML) approach for the estimations of four fundamental parameters, namely, the Hubble constant ($H_0$), matter ($\Omega_{0m}$), curvature ($\Omega_{0k}$) and vacuum ($\Omega_{0\Lambda}$)…

宇宙学与河外天体物理 · 物理学 2024-10-10 Srikanta Pal , Rajib Saha

The Hubble tension, a persistent discrepancy between early and late Universe measurements of $H_0$, poses a significant challenge to the standard cosmological model. In this work, we present a new Bayesian hierarchical framework designed to…

宇宙学与河外天体物理 · 物理学 2025-09-12 Nathalia M. N. da Rocha , Andre L. B. Ribeiro , Francisco B. S. Oliveira

We compare and combine likelihood functions of the cosmological parameters Omega_m, h and sigma_8 from the CMB, type Ia supernovae and from probes of large scale structure. We include the recent results from the CMB experiments BOOMERANG…

天体物理学 · 物理学 2007-05-23 S. L. Bridle

Well-established methods for the solution of stochastic partial differential equations (SPDEs) typically struggle in problems with high-dimensional inputs/outputs. Such difficulties are only amplified in large-scale applications where even…

机器学习 · 统计学 2019-09-10 Constantin Grigo , Phaedon-Stelios Koutsourelakis

This paper addresses the challenges of efficiently fine-tuning large language models (LLMs) by exploring data efficiency and hyperparameter optimization. We investigate the minimum data required for effective fine-tuning and propose a novel…

计算与语言 · 计算机科学 2024-07-22 Michael Oliver , Guan Wang

Cosmological models and their parameters are widely debated, especially about whether the current discrepancy between the values of the Hubble constant, $H_{0}$, obtained by type Ia supernovae (SNe Ia), and the Planck data from the Cosmic…

Strongly lensed quasar systems with time delay measurements provide "time delay distances", which are a combination of three angular diameter distances and serve as powerful tools to determine the Hubble constant $H_0$. However, current…

宇宙学与河外天体物理 · 物理学 2019-12-18 Kai Liao , Arman Shafieloo , Ryan E. Keeley , Eric V. Linder

Hubble tension is a problem in one-dimensional (1D) posteriors, since local $H_0$ determinations are only sensitive to a single parameter. Projected 1D posteriors for $\Lambda$CDM cosmological parameters become more non-Gaussian with…

宇宙学与河外天体物理 · 物理学 2025-01-06 Eoin Ó Colgáin , Saeed Pourojaghi , M. M. Sheikh-Jabbari , Darragh Sherwin

We present a method for calculating large numbers of power spectra C_l and P(k) that accelerates CMBfast by a factor around 10^3 without appreciable loss of accuracy, then apply it to constrain 11 cosmological parameters from current Cosmic…

天体物理学 · 物理学 2009-10-07 Max Tegmark , Matias Zaldarriaga , Andrew J. S. Hamilton

Confidence estimation can improve the reliability of melody estimation by indicating which predictions are likely incorrect. The existing classification-based approach provides confidence for predicted pitch classes but fails to capture the…

音频与语音处理 · 电气工程与系统科学 2025-11-07 Kavya Ranjan Saxena , Vipul Arora

We present model-marginalized limits on the six standard $\Lambda$CDM cosmological parameters ($\Omega_{\rm c} h^2$, $\Omega_{\rm b} h^2$, $\theta_{\rm MC}$, $\tau_{\rm reio}$, $n_s$ and $A_s$), as well as on selected derived quantities…

宇宙学与河外天体物理 · 物理学 2025-01-29 Stefano Gariazzo , William Giarè , Olga Mena , Eleonora Di Valentino

In our recent work [1] on lattice QCD calculation of the baryon leading-twist LCDAs within the framework of LaMET, a novel hybrid renormalization scheme is implemented for octet baryon quasi-DAs, yielding reliable results across both…

高能物理 - 格点 · 物理学 2026-05-15 Mu-Hua Zhang

In Bayesian statistics, one's prior beliefs about underlying model parameters are revised with the information content of observed data from which, using Bayes' rule, a posterior belief is obtained. A non-trivial example taken from the…

高能物理 - 唯象学 · 物理学 2007-05-23 J. Charles , A. Hocker , H. Lacker , F. R. Le Diberder , S. T'Jampens

We investigate in detail some popular cosmological models in light of the latest observational data, including the Union2.1 supernovae compilation, the baryon acoustic oscillation measurements from the WiggleZ Dark Energy Survey, the cosmic…

宇宙学与河外天体物理 · 物理学 2015-06-05 Ke Shi , Yongfeng Huang , Tan Lu

We investigate how the uncertainty on the Hubble constant (H_0) affects the uncertainty in the Equation of State (EOS) of Dark Energy and the total density of the Universe (Omega_tot). We use the approximate relations between the…

天体物理学 · 物理学 2008-11-26 Rob P. Olling

Even though the Hubble constant cannot be significantly determined by the low-redshift Baryon Acoustic Oscillation (BAO) data alone, it can be tightly constrained once the high-redshift BAO data are combined. Combining BAO data from 6dFGS,…

宇宙学与河外天体物理 · 物理学 2015-07-14 Cheng Cheng , Qing-Guo Huang
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