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Related papers: Bayesian Model Comparison of $R_h=ct$ versus $\Lam…

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The present standard model of cosmology, $\Lambda$CDM, contains some intriguing coincidences. Not only are the dominant contributions to the energy density approximately of the same order at the present epoch, but we note that contrary to…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 Pim van Oirschot , Juliana Kwan , Geraint F. Lewis

Strongly gravitationally lensed quasar-galaxy systems allow us to compare competing cosmologies as long as one can be reasonably sure of the mass distribution within the intervening lens. In this paper, we assemble a catalog of 69 such…

Cosmology and Nongalactic Astrophysics · Physics 2018-09-25 Fulvio Melia , Jun-Jie Wei , Xue-Feng Wu

Because the baryon-to-photon ratio eta_{10} is in some doubt, we drop nucleosynthetic constraints on eta_{10} and fit the three cosmological parameters (h, Omega_M, eta_{10}) to four observational constraints: Hubble parameter h_o =…

Astrophysics · Physics 2009-10-30 G. Steigman , N. Hata , J. E. Felten

We constrain flat cosmological models with a joint likelihood analysis of a new compilation of data from the cosmic microwave background (CMB) and from the 2dF Galaxy Redshift Survey (2dFGRS). Fitting the CMB alone yields a known degeneracy…

Using the Bayesian theory of model comparison, a new cosmological model due to John and Joseph [M. V. John and K. Babu Joseph, Phys. Rev. D 61, 87304 (2000)] is compared with the standard \Omega_{\Lambda} \neq 0 cosmological model. Their…

Astrophysics · Physics 2009-11-07 Moncy V. John , J. V. Narlikar

We analyze a new large-scale ($100h^{-1}$Mpc) numerical hydrodynamic simulation of the popular $\Lambda$CDM cosmological model, including in our treatment dark matter, gas and star-formation, on the basis of standard physical processes. The…

Astrophysics · Physics 2016-05-25 Renyue Cen , Jeremiah P. Ostriker

When photons from distant galaxies and stars pass through our neighboring environment, the wavelengths of the photons would be shifted by our local gravitational potential. This local gravitational redshift effect can potentially have an…

Cosmology and Nongalactic Astrophysics · Physics 2019-09-04 Haoting Xu , Zhiqi Huang , Na Zhang , Yundong Jiang

We show that a combined analysis of CMB anisotropy power spectra obtained by the Planck satellite and luminosity distance data simultaneously excludes a flat universe and a cosmological constant at $99 \%$ CL. These results hold separately…

Cosmology and Nongalactic Astrophysics · Physics 2021-02-17 Eleonora Di Valentino , Alessandro Melchiorri , Joseph Silk

We analyse the possibility that our Universe could be described by the model recently proposed by Melia & Shevchuk (2012), where the Hubble scale R_h=c/H is at all times equal to the distance ct that light has travelled since the Big Bang.…

Cosmology and Nongalactic Astrophysics · Physics 2012-08-28 Maciej Bilicki , Marina Seikel

Despite the ability of the cosmological concordance model ($\Lambda$CDM) to describe the cosmological observations exceedingly well, power law expansion of the Universe scale radius, $R(t)\propto t^n$, has been proposed as an alternative…

The $\nu$HDM is the only cosmological model based on Milgromian Dynamics (MOND) with available structure formation simulations. While MOND accounts for galaxies, with a priori predictions for spirals and ellipticals, a light sterile…

Cosmology and Nongalactic Astrophysics · Physics 2025-06-25 Nick Samaras , Sebastian Grandis , Pavel Kroupa

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…

Cosmology and Nongalactic Astrophysics · Physics 2011-03-11 Cong Ma , Tong-Jie Zhang

Baryon Acoustic Oscillations (BAO) involve measuring the spatial distribution of galaxies to determine the growth rate of cosmic structure. We derive constraints on cosmological parameters from $17$ uncorrelated BAO measurements that were…

Cosmology and Nongalactic Astrophysics · Physics 2021-03-10 David Benisty , Denitsa Staicova

We use the redshift Hubble parameter $H(z)$ data derived from relative galaxy ages, distant type Ia supernovae (SNe Ia), the Baryonic Acoustic Oscillation (BAO) peak, and the Cosmic Microwave Background (CMB) shift parameter data, to…

Cosmology and Nongalactic Astrophysics · Physics 2011-01-27 Tian Lan , Yan Gong , Hao-Yi Wan , Tong-Jie Zhang

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…

Cosmology and Nongalactic Astrophysics · Physics 2024-09-12 Chen Sun , Manuel A. Buen-Abad , JiJi Fan

The standard cosmological model, LCDM, provides an excellent fit to Cosmic Microwave Background (CMB) data. However, the model has well known problems. For example, the cosmological constant, is fine-tuned to 1 part in 10^100 and the cold…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-18 T. Shanks , R. W. F. Johnson , J. A. Schewtschenko , J. R. Whitbourn

Cosmological observables could be used to construct cosmological models, however, a fixed number of observables limited on the light cone is not enough to uniquely determine a certain model. A reconstructed spherically symmetric,…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-17 Siqi Liu , Tong-Jie Zhang

The Hubble tension that the standard $\Lambda$CDM model is suffering from can be resolved with pre-recombination early dark energy. We present the first constraint on the tensor-to-scalar ratio $r$ in corresponding Hubble-tension-free…

Cosmology and Nongalactic Astrophysics · Physics 2022-09-07 Gen Ye , Yun-Song Piao

Bayesian model selection poses two main challenges: the specification of parameter priors for all models, and the computation of the resulting Bayes factors between models. There is now a large literature on automatic and objective…

Methodology · Statistics 2016-08-11 Leonhard Held , Daniel Sabanés Bové , Isaac Gravestock

A large number of studies, all using Bayesian parameter inference from Markov Chain Monte Carlo methods, have constrained the presence of a decaying dark matter component. All such studies find a strong preference for either very long-lived…

Cosmology and Nongalactic Astrophysics · Physics 2022-11-04 Emil Brinch Holm , Laura Herold , Steen Hannestad , Andreas Nygaard , Thomas Tram