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We investigate the conditions under which cosmological variations in physical `constants' and scalar fields are detectable on the surface of local gravitationally-bound systems, such as planets, in non-spherically symmetric background…

General Relativity and Quantum Cosmology · Physics 2011-07-19 Douglas J. Shaw , John D. Barrow

We present a new, cosmologically model-independent, statistical analysis of the Pantheon+ type Ia supernovae spectroscopic dataset, improving a standard methodology adopted by Lane et al. We use the Tripp equation for supernova…

Cosmology and Nongalactic Astrophysics · Physics 2024-12-20 Antonia Seifert , Zachary G. Lane , Marco Galoppo , Ryan Ridden-Harper , David L. Wiltshire

The relation between halo mass, M, and concentration, c, is a critical component in our understanding of the structure of dark matter halos. While numerous models for this relation have been proposed, almost none of them attempt to derive…

Cosmology and Nongalactic Astrophysics · Physics 2019-01-31 Benedikt Diemer , Michael Joyce

The standard interpretation of the observed redshifted spectra and luminosities towards distant astrophysical objects is that the universe is expanding, an inference which is found to be consistent with other cosmological probes as well.…

General Physics · Physics 2013-08-06 Meir Shimon

We re-examine the observational evidence for large-scale (4 Mpc) galactic conformity in the local Universe, as presented in Kauffmann et al. (2013). We show that a number of methodological features of their analysis act to produce a…

Astrophysics of Galaxies · Physics 2017-09-06 Larry P. T. Sin , Simon J. Lilly , Bruno M. B. Henriques

We revise the statistical properties of the primordial cosmological density anisotropies that, at the time of matter radiation equality, seeded the gravitational development of large scale structures in the, otherwise, homogeneous and…

High Energy Physics - Phenomenology · Physics 2008-11-26 David H. Oaknin

Based on the cosmological principle only, the method of describing the evolution of the Universe, called cosmography, is in fact a kinematics of cosmological expansion. The effectiveness of cosmography lies in the fact that it allows, based…

General Relativity and Quantum Cosmology · Physics 2018-12-07 Yu. L. Bolotin , V. A. Cherkaskiy , O. Yu. Ivashtenko , M. I. Konchatnyi , L. G. Zazunov

The absence of an identified consequence at solar system scale of the cosmological space expansion is usually explained considering that space expansion does not affect local anysotropies in matter distribution. This can also be explained…

General Physics · Physics 2007-05-23 A. Gouveia Oliveira , Rodrigo de Abreu

A wide range of large scale observations hint towards possible modifications on the standard cosmological model which is based on a homogeneous and isotropic universe with a small cosmological constant and matter. These observations, also…

Cosmology and Nongalactic Astrophysics · Physics 2014-01-21 Leandros Perivolaropoulos

The spatial arrangement of galaxies (of satellites on a scale of 100kpc) as well as their three-dimensional distribution in galaxy groups such as the Local Group (on a scale of 1Mpc), the distribution of galaxies in the nearby volume of…

Cosmology and Nongalactic Astrophysics · Physics 2016-10-14 Pavel Kroupa

Requiring all massless elementary fields to have conformal scaling symmetry removes a conflict between gravitational theory and the quantum theory of elementary particles and fields. Extending this postulate to the scalar field of the Higgs…

General Physics · Physics 2011-05-12 Robert K. Nesbet

Astronomical observations reveal hierarchical structures in the Universe, from galaxies, groups of galaxies, clusters and superclusters, to filaments and voids. On the largest scales it seems that some kind of statistical homogeneity can be…

General Relativity and Quantum Cosmology · Physics 2017-05-23 Krzysztof Bolejko , Mikołaj Korzyński

We investigate the existence of minisuperspace description for the homogeneous cosmological field equations within the framework of symmetric teleparallel $f(Q)$-gravity. We consider the background space to be described by the isotropic…

General Relativity and Quantum Cosmology · Physics 2023-12-19 A. Paliathanasis , N. Dimakis , T. Christodoulakis

It is generally believed that inflationary cosmology explains the isotropy, large scale homogeneity and flatness as well as predicting the deviations from homogeneity of our universe. We show that this is not the only cosmology which can…

High Energy Physics - Theory · Physics 2007-05-23 J. W. Moffat

Modern cosmology is based on the cosmological principle, which states that the Universe is statistically homogeneous and isotropic. When applied in its strict -- rather than statistical -- sense, the cosmological principle leads to the…

Cosmology and Nongalactic Astrophysics · Physics 2025-09-03 Pierre Fleury

If our observable Universe is only a tiny region of a vastly larger and conformally older spacetime, then the usual formulations of the classical flatness and horizon problems of the Hot Big Bang can be reinterpreted as artifacts…

General Relativity and Quantum Cosmology · Physics 2026-02-12 Meir Shimon

The homogeneous, isotropic, and flat $\Lambda$CDM universe favored by observations of the cosmic microwave background can be described using only Euclidean geometry, locally correct Newtonian mechanics, and the basic postulates of special…

Cosmology and Nongalactic Astrophysics · Physics 2018-06-27 J. J. Condon , A. M. Matthews

A scale-dependent cosmology is proposed in which the Robertson-Walker metric and the Einstein equation are modified in such a way that $\Omega_0$, $H_0$ and the age of the Universe all become scale-dependent. Its implications on the…

High Energy Physics - Phenomenology · Physics 2009-10-28 C. W. Kim , T. H. Lee , J. Song

Six challenges for the standard cosmological model $\Lambda$CDM are listed, which arise when comparing theoretical predictions with observational data on scales of ~1 Mpc. Different parameters of luminous and dwarf galaxies in the local…

General Relativity and Quantum Cosmology · Physics 2026-05-29 I. D. Karachentsev

The fundamental laws of physics are required to be invariant under local spatial scale change. In 3-dimensional space, this leads to a variation in Planck constant \hbar and speed of light c. They vary as \hbar ~ a^(1/2) and c ~ a^(-1/2), a…

General Physics · Physics 2013-02-28 Hoang K. Nguyen