English
Related papers

Related papers: A new analytical solution for the distance modulus…

200 papers

We use the dispersion measure (DM) and redshift measurements of 24 localized fast radio bursts (FRBs) to compare cosmological models and investigate the Hubble tension. Setting a flat prior on the DM contribution from the Milky Way's halo,…

Cosmology and Nongalactic Astrophysics · Physics 2023-08-14 Jun-Jie Wei , Fulvio Melia

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…

Cosmology and Nongalactic Astrophysics · Physics 2025-04-29 Furkan Şakir Dilsiz , Cemsinan Deliduman , Selinay Sude Binici

The $\Lambda$CDM model provides a good fit to most astronomical observations but harbors large areas of phenomenology and ignorance. With the improvements in the precision and number of observations, discrepancies between key cosmological…

Cosmology and Nongalactic Astrophysics · Physics 2023-02-15 Jian-Ping Hu , Fa-Yin Wang

We suggest that the solution to the cosmological vacuum energy puzzle does not require any new field beyond the standard model, but rather can be explained as a result of the interaction of the infrared sector of the effective theory of…

Cosmology and Nongalactic Astrophysics · Physics 2011-07-13 Federico R. Urban , Ariel R. Zhitnitsky

The most recent cosmological observations indicate that the present universe is flat and vacuum dominated. In such a universe, the distance measurements are always difficult and involve numerical computations. In this paper, it is shown…

Astrophysics · Physics 2007-12-06 T. Wickramasinghe

We present a new measurement of the Hubble Constant H0 and other cosmological parameters based on the joint analysis of three multiply-imaged quasar systems with measured gravitational time delays. First, we measure the time delay of…

The presence of the dark energy allows both the acceleration and the expansion of the universe. In the case of a constant equation of state for dark energy we derived an analytical solution for the Hubble radius in terms of the…

Cosmology and Nongalactic Astrophysics · Physics 2019-09-06 Lorenzo Zaninetti

We calculate the low red-shift Taylor expansion for the luminosity distance for an observer at the center of a spherically symmetric matter inhomogeneity with a non vanishing cosmological constant. We then test the accuracy of the formulas…

Cosmology and Nongalactic Astrophysics · Physics 2014-05-09 Antonio Enea Romano , Pisin Chen

Recently, cosmology has seen a surge in alternative models that purport to solve the discrepancy between the values of the Hubble constant $H_0$ as measured by cosmological microwave background anisotropies and local supernovae,…

Cosmology and Nongalactic Astrophysics · Physics 2024-04-01 Jonas El Gammal , Sven Günther , Emil Brinch Holm , Andreas Nygaard

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 performed a systematic and comprehensive estimate of the Hubble constant $H_0$ via the Sunyaev-Zel'dovich temperature decrement and the X-ray measurements for clusters up to the redshift $z=0.541$, with particular attention to its…

Astrophysics · Physics 2015-06-24 Shiho Kobayashi , Shin Sasaki , Yasushi Suto

We present a simultaneous analysis of 18 galaxy lenses with time delay measurements. For each lens we derive mass maps using pixelated simultaneous modeling with shared Hubble constant. We estimate the Hubble constant to be 66_{-4}^{+6}…

Cosmology and Nongalactic Astrophysics · Physics 2010-10-05 Danuta Paraficz , Jens Hjorth

In the realm of the $\omega$CDM cosmological model with quiescence or quintessence as the dark energy, characterized by $\omega>-1$, there exists a fixed value of $H(z)$ at $z=-1$, devoid of dependency on other cosmological parameters. To…

Cosmology and Nongalactic Astrophysics · Physics 2024-07-16 Cheqiu Lyu , Wei Hong , Tong-Jie Zhang

We make the hypothesis that the velocity of light and the expansion of the universe are two aspects of one single concept connecting space and time in the expanding universe. We show that solving Friedman's equations with that…

Astrophysics · Physics 2009-06-23 J. -M. Vigoureux , P. Vigoureux , B. Vigoureux

In this work, we obtain measurements of the Hubble constant in the context of modified gravity theories. We set up our theoretical framework by considering viable cosmological $f(R)$ and $f(T)$ models, and we analyzed them through the use…

Cosmology and Nongalactic Astrophysics · Physics 2020-05-07 Rocco D'Agostino , Rafael C. Nunes

The $\Lambda$CDM model faces several tensions with recent cosmological data and their increased accuracy. The mismatch between the values of the Hubble constant $H_0$ obtained from direct distance ladder measurements and from the cosmic…

Cosmology and Nongalactic Astrophysics · Physics 2024-05-03 Alain Blanchard , Jean-Yves Héloret , Stéphane Ilić , Brahim Lamine , Isaac Tutusaus

Renormalized cosmological models based on the general-relativistic second-order perturbation theory were proposed in the previous papers to solve a tension on the observed Hubble constants. The cosmological random adiabatic fluctuations…

General Relativity and Quantum Cosmology · Physics 2020-01-27 Kenji Tomita

Despite the remarkable success of the $\Lambda$Cold Dark Matter ($\Lambda$CDM) cosmological model, a growing discrepancy has emerged (currently measured at the level of $\sim 4-6 \sigma$) between the value of the Hubble constant $H_0$…

Cosmology and Nongalactic Astrophysics · Physics 2022-09-07 Nils Schöneberg , Guillermo Franco Abellán , Andrea Pérez Sánchez , Samuel J. Witte , Vivian Poulin , Julien Lesgourgues

Within the $\Lambda$CDM cosmological model, the absolute value of Einstein's cosmological constant $\Lambda$, sometimes expressed as the gravitating mass-energy density $\rho_\Lambda$ of the physical vacuum, is a fundamental constant of…

Cosmology and Nongalactic Astrophysics · Physics 2022-06-22 J. Prat , C. Hogan , C. Chang , J. Frieman

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