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Related papers: A Tale of Two Distances

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Tensions between cosmological parameters derived through different channels can be a genuine signature of new physics that $\Lambda$CDM as the standard model is not able to reproduce, in particular in the missing consistency between…

Cosmology and Nongalactic Astrophysics · Physics 2025-02-20 Benedikt Schosser , Pedro Riba Mello , Miguel Quartin , Bjoern Malte Schaefer

Distance-redshift diagrams probe expansion history of the Universe. We show that the stellar mass-binding energy (massE) relation of galaxies proposed in our previous study offers a new distance ruler at cosmic scales. By using elliptical…

Cosmology and Nongalactic Astrophysics · Physics 2022-09-05 Yong Shi , Yanmei Chen , Shude Mao , Qiusheng Gu , Tao Wang , Xiaoyang Xia , Zhi-Yu Zhang

One of the main goals of physical cosmology is to reconstruct the expansion history of the universe and finding the actual model of dark energy. In this article I review the difficulties of understanding dark energy and discuss about two…

Cosmology and Nongalactic Astrophysics · Physics 2014-01-30 Arman Shafieloo

Cosmological observations indicate that our universe is flat and dark energy (DE) dominated at present. The luminosity distance plays an important role in the investigation of the evolution and structure of the universe. Nevertheless, the…

Cosmology and Nongalactic Astrophysics · Physics 2012-08-24 De-Zi Liu , Nan-Nan Yue , Xiao-Lei Meng , Tong-Jie Zhang , Zhi-Liang Yang

Some remarkable examples of alternative cosmological theories are reviewed here, ranging from a compilation of variations on the Standard Model through the more distant quasi-steady-state cosmology, plasma cosmology, or universe models as a…

Cosmology and Nongalactic Astrophysics · Physics 2022-08-17 Martin Lopez-Corredoira , Louis Marmet

The Friedmann equation is derived for a Newtonian universe. Changing mass density to energy density gives exactly the Friedmann equation of general relativity. Accounting for work done by pressure then yields the two Einstein equations that…

Astrophysics · Physics 2015-06-24 Thomas F. Jordan

We show that various scalar field models of dark energy predict degenerate luminosity distance history of the Universe and thus cannot be distinguished by supernovae measurements alone. In particular, models with a vanishing cosmological…

High Energy Physics - Phenomenology · Physics 2009-11-07 Irit Maor , Ram Brustein

The results of different analyses of the dynamical parameters of the Universe are converging towards agreement. Remaining disagreements reflect systematic errors coming either from the observations or from differences in the methods of…

Astrophysics · Physics 2007-05-23 Matts Roos , S. M. Harun-or-Rashid

We calculate the systematic inhomogeneity-induced correction to the cosmological constant that one would infer from an analysis of the luminosities and redshifts of Type Ia supernovae, assuming a homogeneous universe. The calculation…

Astrophysics · Physics 2008-12-18 R. Ali Vanderveld , Eanna E. Flanagan , Ira Wasserman

Even though the Dark Energy Spectroscopic Instrument (DESI) mission does not exclude a dynamical dark energy evolution, the concordance paradigm, i.e., the $\Lambda$CDM model, remains statistically favored, as it depends on the fewest…

Cosmology and Nongalactic Astrophysics · Physics 2024-11-08 Anna Chiara Alfano , Orlando Luongo , Marco Muccino

In recent years, the Lambda Cold Dark Matter (LCDM) model, which has been pivotal in cosmological studies, has faced significant challenges due to emerging observational and theoretical inconsistencies. This paper explores alternative…

Cosmology and Nongalactic Astrophysics · Physics 2025-02-04 Dharmendra Kumar , Ayan Mitra , Shahnawaz A. Adil , Anjan A. Sen

We demonstrate that constraints on cosmological parameters from the distribution of clusters as a function of redshift (dN/dz) are complementary to accurate angular diameter distance (D_A) measurements to clusters, and their combination…

Astrophysics · Physics 2009-11-10 S. M. Molnar , Z. Haiman , M. Birkinshaw , R. F. Mushotzky

In this paper, we present a kinematic analysis of the Universe's expansion history using cosmography, with a particular emphasis on the jerk parameter $j_0$, which is equal to one in the standard $\Lambda$CDM scenario. We use distance…

Cosmology and Nongalactic Astrophysics · Physics 2025-10-02 Gabriel Rodrigues , Rayff de Souza , Jailson Alcaniz

We use the angular power spectrum of the Cosmic Microwave Background, measured during the North American test flight of the BOOMERANG experiment, to constrain the geometry of the universe. Within the class of Cold Dark Matter models, we…

We study some cosmological constraints on the two phenomenological models of oscillating dark energy. In these scenarios, the equation of state of dark energy varies periodically and may provide a way to unify the early acceleration…

Astrophysics · Physics 2009-06-23 Deepak Jain , Abha Dev , J. S. Alcaniz

We examine the Pantheon supernovae distance data compilation in a model independent analysis to test the validity of cosmic history reconstructions beyond the concordance $\Lambda$CDM cosmology. Strong deviations are allowed by the data at…

Cosmology and Nongalactic Astrophysics · Physics 2019-03-19 Benjamin L'Huillier , Arman Shafieloo , Eric V. Linder , Alex G. Kim

After briefly reviewing the good agreement between large-scale observations and the predictions of the now-standard CDM theory and problems with the MOND alternative, I summarize several of the main areas of possible disagreement between…

Astrophysics · Physics 2008-11-26 Joel R. Primack

A recently proposed Asymptotically Safe cosmology provides an elegant mechanism towards understanding the nature of dark energy and its associated cosmic coincidence problem. The underlying idea is that the accelerated expansion of the…

Cosmology and Nongalactic Astrophysics · Physics 2019-03-06 Fotios K. Anagnostopoulos , Spyros Basilakos , Georgios Kofinas , Vasilios Zarikas

We use the Allen et al. (2008) galaxy cluster gas mass fraction versus redshift data to constrain parameters of three different dark energy models: a cosmological constant dominated one ($\Lambda$CDM); the XCDM parameterization of dark…

Astrophysics · Physics 2010-11-11 Lado Samushia , Bharat Ratra

We present the first cosmological constraints using only the observed photometry of galaxies. Villaescusa-Navarro et al. (2022; arXiv:2201.02202) recently demonstrated that the internal physical properties of a single simulated galaxy…

Cosmology and Nongalactic Astrophysics · Physics 2023-10-16 ChangHoon Hahn , Francisco Villaescusa-Navarro , Peter Melchior , Romain Teyssier
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