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Related papers: A look at the Hubble speed from first principles

200 papers

Although cosmologists have been trying to determine the value of the Hubble constant for nearly 65 years, they have only succeeded in limiting the range of possibilities: most of the current observational determinations place the Hubble…

Astrophysics · Physics 2009-10-22 J. G. Bartlett , A. Blanchard , J. Silk , M. S. Turner

Using comoving distance $d_c$ and angular diameter distance $d_A$, we recalculate parameters describing kinematical state of the universe, still combining the kinematical model of universe but not relying on dynamical equations for gravity.…

Cosmology and Nongalactic Astrophysics · Physics 2021-05-27 Hai Huang , Long Huang

We present a cosmological model-independent determination of the Hubble constant, $H_0$, by combining time-delay measurements from seven TDCOSMO systems, Einstein radius measurements, and Type Ia Supernovae data sourced from the Pantheon+…

Cosmology and Nongalactic Astrophysics · Physics 2025-05-28 L. R. Colaço , R. F. L. Holanda , Z. C. Santana , R. Silva

This paper presents a new model-independent constraint on the Hubble constant ($H_0$) by anchoring relative distances from Type Ia supernovae (SNe Ia) observations to absolute distance measurements from time-delay strong Gravitational…

Cosmology and Nongalactic Astrophysics · Physics 2025-03-13 L. R. Colaço

Current measurements of the Hubble constant $H_0$ on scale less than $\sim100$ Mpc appear to be controversial, while the observations made at high redshift seem to provide a relatively low value. On the other hand, the Hubble expansion is…

Astrophysics · Physics 2009-10-28 Xiang-Ping Wu , Bo Qin , Li-Zhi Fang

Considerable progress has been made in determining the Hubble constant over the past two decades. We discuss the cosmological context and importance of an accurate measurement of the Hubble constant, and focus on six high-precision…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 Wendy L. Freedman , Barry F. Madore

In this paper, we go further and propose a cosmological model-independent approach to simultaneously determine the Hubble constant and cosmic curvature with strong lensing time-delay measurements, without any prior assumptions regarding the…

Cosmology and Nongalactic Astrophysics · Physics 2024-02-19 Tonghua Liu , Shuo Cao , Sixuan Zhang , Chenfa Zheng , Wuzheng Guo

The Megamaser Cosmology Project inferred a value for the Hubble constant given by $H_0=73.9 \pm 3.0 $ km/sec/Mpc. This value was obtained using Bayesian inference by marginalizing over six nuisance parameters, corresponding to the…

Instrumentation and Methods for Astrophysics · Physics 2025-06-23 Shubham Barua , Vyaas Ramakrishnan , Shantanu Desai

In this paper, we make a comprehensive determination of the Hubble constant $H_0$ by using two parameters - the B-V color and the rate of decline $\Delta m_{15}$ - to simultaneously standardize the luminosities of all nearby…

Astrophysics · Physics 2009-10-31 R. Tripp , D. Branch

We perform the improved constraints on the Hubble constant $H_0$ by using the model-independent method, Gaussian Processes. Utilizing the latest 36 $H(z)$ measurements, we obtain $H_0=69.21\pm3.72$ km s$^{-1}$ Mpc$^{-1}$, which is…

General Relativity and Quantum Cosmology · Physics 2016-10-06 Deng Wang , Xin-He Meng

A measurement of the expansion rate of the Universe (that is the Hubble constant, H0) is derived here using the gamma-ray attenuation observed in the spectra of gamma-ray sources produced by the interaction of extragalactic gamma-ray…

Cosmology and Nongalactic Astrophysics · Physics 2019-08-19 A. Domínguez , F. Prada

The final efforts of the HST Key Project on the Extragalactic Distance Scale are presented. Four distance indicators, the Surface Brightness Fluctuation method, the Fundamental Plane for early-type galaxies, the Tully-Fisher relation and…

The Hubble constant ($H_0$), which represents the expansion rate of the Universe, is one of the most important cosmological parameters. The recent measurements of $H_0$ using the distance ladder methods such as Type Ia Supernovae (SNe Ia)…

Cosmology and Nongalactic Astrophysics · Physics 2023-06-14 Rahul Kumar Thakur , Shashikant Gupta , Rahul Nigam , PK Thiruvikraman

We present a numerical method to estimate the lensing parameters and the Hubble constant H_0 from quadruply imaged gravitational lens systems. The lens galaxy is modeled using both separable deflection potentials and constant mass-to-light…

Astrophysics · Physics 2009-11-10 C. Tortora , E. Piedipalumbo , V. F. Cardone

Gravitational lensing is now widely and successfully used to study a range of astronomical phenomena, from individual objects, like galaxies and clusters, to the mass distribution on various scales, to the overall geometry of the Universe.…

Astrophysics · Physics 2007-05-23 Liliya L. R. Williams , Paul L. Schechter

Since the launch of the Hubble Space Telescope nine years ago, Cepheid distances to 25 galaxies have been determined for the purpose of calibrating secondary distance indicators. A variety of these can now be calibrated, and the…

Measurements of the Hubble constant, $H_0$, from the cosmic distance ladder are currently in tension with the value inferred from Planck observations of the CMB and other high redshift datasets if a flat $\Lambda$CDM cosmological model is…

Cosmology and Nongalactic Astrophysics · Physics 2021-01-18 Eric J. Baxter , Blake D. Sherwin

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…

Cosmology and Nongalactic Astrophysics · Physics 2019-12-18 Kai Liao , Arman Shafieloo , Ryan E. Keeley , Eric V. Linder

In cold dark matter models, a galaxy's dark matter halo is more spatially extended than its stars. However, even though the five well-constrained gravitational lenses with time delay measurements must have similar dark matter distributions,…

Astrophysics · Physics 2007-05-23 C. S. Kochanek

Many of the fundamental physical constants in Physics, as a discipline, are measured to exquisite levels of precision. The fundamental constants that define Cosmology, however, are largely determined via a handful of independent techniques…