中文
相关论文

相关论文: High Redshift $\Lambda$CDM Cosmology: To Bin or no…

200 篇论文

Many scientific investigations of photometric galaxy surveys require redshift estimates, whose uncertainty properties are best encapsulated by photometric redshift (photo-z) posterior probability density functions (PDFs). A plethora of…

Several models based on General Relativity and Modified Gravity aim to reproduce the observed universe with precision comparable to the flat-$\Lambda$CDM cosmological model. In this study, we investigate the consistency of some of these…

宇宙学与河外天体物理 · 物理学 2025-12-05 Fernanda Oliveira , Bruno Ribeiro , Wiliam S. Hipólito-Ricaldi , Felipe Avila , Armando Bernui

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…

宇宙学与河外天体物理 · 物理学 2020-01-15 Velasquez-Toribio , A. M , Magnago , A. dos R

In the present study, we use the DES Y3 catalog of LRG to incorporate the realistic galaxies' redshift Probability Distribution Function(PDF) into the correlation function cosmological model. We used four different photo-z estimators ANNz2,…

宇宙学与河外天体物理 · 物理学 2026-04-06 Paula S. Ferreira , Ribamar R. R. Reis

In the paper, we consider two models in which dark energy is coupled with either dust matter or dark matter, and discuss the conditions that allow more time for structure formation to take place at high redshifts. These models are expected…

宇宙学与河外天体物理 · 物理学 2021-03-08 Shulei Cao , Tong-Jie Zhang , Xinya Wang , Tingting Zhang

Using a suite of self-similar cosmological simulations, we measure the probability distribution functions (PDFs) of real-space density, redshift-space density, and their geometric mean. We find that the real-space density PDF is…

宇宙学与河外天体物理 · 物理学 2022-04-27 Huanqing Chen , Nickolay Y. Gnedin , Philip Mansfield

We perform a model-independent reconstruction of the angular diameter distance ($D_{A}$) using the Multi-Task Gaussian Process (MTGP) framework with DESI-DR1 BAO and DES-SN5YR datasets. We calibrate the comoving sound horizon at the baryon…

宇宙学与河外天体物理 · 物理学 2025-03-13 Purba Mukherjee , Anjan A Sen

The Hubble crisis is the discrepancy in the values of the Hubble constant inferred from diverse observations in the late and early Universe, being of the order 5$\sigma$. Instead of resolution, the conflict is getting larger with further…

宇宙学与河外天体物理 · 物理学 2025-04-29 Furkan Şakir Dilsiz , Cemsinan Deliduman , Selinay Sude Binici

We study the reconstructed deceleration parameter splitting the data in different redshift bins, fitting both a cosmographic luminosity distance and also assuming a flat $\Lambda$CDM model, using the Pantheon+ sample of type Ia supernova…

宇宙学与河外天体物理 · 物理学 2023-04-20 Erick Pastén , Victor Cárdenas

The cosmographic approach is gaining considerable interest as a model-independent technique able to describe the late expansion of the universe. Indeed, given only the observational assumption of the cosmological principle, it allows to…

宇宙学与河外天体物理 · 物理学 2019-12-11 Micol Benetti , Salvatore Capozziello

A number of recent, low-redshift, lensing measurements hint at a universe in which the amplitude of lensing is lower than that predicted from the $\Lambda$CDM model fit to the data of the Planck CMB mission. Here we use the auto- and…

宇宙学与河外天体物理 · 物理学 2021-12-22 Alex Krolewski , Simone Ferraro , Martin White

I investigate through simulations the redshift dependence of several lensing measures for two cosmological models, a flat universe with a cosmological constant (\LambdaCDM), and an open universe (OCDM). I argue that quintessence models can…

天体物理学 · 物理学 2007-05-23 Antonio C. C. Guimarães

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…

宇宙学与河外天体物理 · 物理学 2011-03-11 Cong Ma , Tong-Jie Zhang

Accurately measuring the Hubble parameter is vital for understanding the expansion history and properties of the universe. In this paper, we propose a new method that supplements the covariance between redshift pairs to improve the…

宇宙学与河外天体物理 · 物理学 2024-01-23 Jian-Chen Zhang , Yu Hu , Kang Jiao , Hong-Feng Wang , Yuan-Bo Xie , Bo Yu , Li-Li Zhao , Tong-Jie Zhang

Cosmological constraints are usually derived under the assumption of a $6$ parameters $\Lambda$-CDM theoretical framework or simple one-parameter extensions. In this paper we present, for the first time, cosmological constraints in a…

宇宙学与河外天体物理 · 物理学 2015-12-30 Eleonora Di Valentino , Alessandro Melchiorri , Joseph Silk

Measurements of the Hubble constant, and more generally measurements of the expansion rate and distances over the interval $0 < z < 1$, appear to be inconsistent with the predictions of the standard cosmological model ($\Lambda$CDM) given…

宇宙学与河外天体物理 · 物理学 2020-03-04 Lloyd Knox , Marius Millea

Upcoming surveys of the large-scale structure of our Universe will employ a large coverage area of about half of the sky and will significantly increase the observational depth. With these surveys, we will be able to cross-correlate CMB…

宇宙学与河外天体物理 · 物理学 2024-09-10 Chandra Shekhar Saraf , Pawel Bielewicz

We use the Simon, Verde, & Jimenez (2005) determination of the redshift dependence of the Hubble parameter to constrain cosmological parameters in three dark energy cosmological models. We consider the standard $\Lambda$CDM model, the XCDM…

天体物理学 · 物理学 2011-02-11 Lado Samushia , Bharat Ratra

The Hubble diagram of quasars, as candidates to ``standardizable" candles, has been used to measure the expansion history of the Universe at late times, up to very high redshifts ($z \sim 7$). It has been shown that this history, as…

宇宙学与河外天体物理 · 物理学 2024-09-12 Chen Sun , Manuel A. Buen-Abad , JiJi Fan