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Recently it has been noted by Di Valentino, Melchiorri and Silk (2019) that the enhanced lensing signal relative to that expected in the spatially flat $\Lambda$CDM model poses a possible crisis for the…

General Relativity and Quantum Cosmology · Physics 2020-08-12 Asta Heinesen , Thomas Buchert

Contemporary multidimensional cosmological theories predict different variations of fundamental physical constants in course of the cosmological evolution. On the basis of the QSO spectra analysis, we show that the fine-structure constant…

Astrophysics · Physics 2007-05-23 D. A. Varshalovich , A. Y. Potekhin , A. V. Ivanchik , V. E. Panchuk , K. M. Lanzetta

It is shown that a first-order cosmological perturbation theory for the open, flat and closed Friedmann-Lema\^itre-Robertson-Walker universes admits one, and only one, gauge-invariant variable which describes the perturbation to the energy…

General Relativity and Quantum Cosmology · Physics 2014-10-02 P. G. Miedema , W. A. van Leeuwen

Observational evidence consistently shows that the universe is spatially flat and undergoes Lorentzian time dilation as a function of redshift. In combination, such discoveries suggest that a Minkowskian description of cosmology might be…

General Physics · Physics 2024-10-14 Artur Novais , A. L. B. Ribeiro

A higher value of Hubble constant has been obtained from measurements with nearby Type Ia supernovae, than that obtained at much higher redshift. With the peculiar motions of their hosts, we find that the matter content at such low redshift…

Cosmology and Nongalactic Astrophysics · Physics 2013-07-25 Shuang-Nan Zhang , Yin-Zhe Ma

A class of coordinate systems is found for Friedmann Cosmologies with local gravity such that it is possible to formulate quantum theory over astronomical and cosmological distances. When light from distance objects is treated as a quantum…

General Physics · Physics 2009-04-28 Charles Francis

We study the effects of the time evolution of the matter-gravity coupling on the luminosity distance, showing it can provide a natural explanation to the apparent Hubble tension. The gravitational coupling evolution induces a modification…

General Relativity and Quantum Cosmology · Physics 2025-09-03 Antonio Enea Romano

This paper makes the simple observation that a fundamental length, or cutoff, in the context of Friedmann-Lema\^itre-Robertson-Walker (FRW) cosmology implies very different things than for a static universe. It is argued that it is…

Cosmology and Nongalactic Astrophysics · Physics 2011-01-13 Marvin Weinstein

Aims. We constrain a hypothetical variation in the fundamental physical constants over the course of cosmic time. Methods. We use unique observations of the CO(7-6) rotational line and the [CI] 3P_2 - 3P_1 fine-structure line towards a…

Cosmology and Nongalactic Astrophysics · Physics 2013-06-12 S. A. Levshakov , F. Combes , F. Boone , I. I. Agafonova , D. Reimers , M. G. Kozlov

From the first observations made by Slipher, our understanding and interpretation of the cosmological redshift was evolving until reaching the current consensus, through the expanding universe and the emergence of modern physical cosmology…

Cosmology and Nongalactic Astrophysics · Physics 2020-02-28 Gabriel R. Bengochea

Redshift drift refers to the phenomena that redshift of cosmic objects is a function of time. Measurement of redshift drift is of fundamental importance in physical cosmology and can be utilized to distinguish different cosmological models.…

General Relativity and Quantum Cosmology · Physics 2020-06-16 Snehasish Bhattacharjee , P. K. Sahoo

In this manuscript, we show that three fundamental building blocks are supporting the Cosmological Principle. The first of them states that there is a special frame in the universe where the spatial geometry is intrinsically homogeneous and…

General Relativity and Quantum Cosmology · Physics 2024-01-05 Leandro G. Gomes

The standard relation between the cosmological redshift and cosmic scale factor underlies cosmological inference from virtually all kinds of cosmological observations, leading to the emergence of the LambdaCDM cosmological model. This…

Cosmology and Nongalactic Astrophysics · Physics 2019-08-08 Radosław Wojtak , Francisco Prada

The cosmological redshifts z in the frequencies of spectral lines from distant galaxies as compared with their values observed in terrestrial laboratories, which are due to the scale factor a(t), frequently are interpret as a…

General Physics · Physics 2011-12-07 Branislav Vlahovic

The standard formulation of General Relativity Theory, in the absence of a cosmological constant, is unable to explain the responsible mechanism for the observed late-time cosmic acceleration. On the other hand, by inserting the…

General Relativity and Quantum Cosmology · Physics 2022-12-26 Raja Solanki , Simran Arora , P. K. Sahoo , P. H. R. S. Moraes

In this work, we present a method for numerically solving the Friedmann equations of modified $f(\mathcal{G})$ gravity in the presence of pressureless matter. This method enables us to predict the redshift behaviour of the Hubble expansion…

General Relativity and Quantum Cosmology · Physics 2024-11-08 Santosh V. Lohakare , Soumyadip Niyogi , B. Mishra

Starting from the revelation of the nature of inertial forces, this article discusses the subdivision of the basic physical concept of space-time and raises questions about the metric of standard cosmology. A new form of particle dynamics…

High Energy Physics - Theory · Physics 2024-06-25 ChiYi Chen

There has been recent interest in the cosmological consequences of energy-momentum-powered gravity models, in which the matter side of Einstein's equations is modified by the addition of a term proportional to some power, $n$, of the…

Cosmology and Nongalactic Astrophysics · Physics 2019-05-29 M. C. F. Faria , C. J. A. P. Martins , F. Chiti , B. S. A. Silva

We investigate a fourth order model of gravity, having a free length parameter, and no cosmological constant or dark energy. We consider cosmological evolution of a flat Friedmann universe in this model for the case that the length…

General Relativity and Quantum Cosmology · Physics 2015-10-14 Shreya Banerjee , Nilesh Jayswal , Tejinder P. Singh

Webb et al. presented preliminary evidence for a time-varying fine-structure constant. We show Teller's formula for this variation to be ruled out within the Einstein-de Sitter universe, however, it is compatible with cosmologies which…

Astrophysics · Physics 2007-05-23 R. W. Kuhne