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Related papers: The Dyer-Roeder distance-redshift relation in inho…

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The influence of mass inhomogeneities on the angular size-redshift test is investigated for a large class of flat cosmological models driven by dark energy plus a cold dark matter component. The results are presented in two steps. First,…

Astrophysics · Physics 2007-09-13 R. C. Santos , J. A. S. Lima

This paper addresses a problem recently raised by Laurent and Nogueira about inhomogeneous Diophantine approximation with coprime integers. As a corollary of our main theorem we obtain an improvement of the best known exponent of…

Number Theory · Mathematics 2012-02-28 Alan Haynes

Cosmography is a phenomenological and relatively model-independent approach to cosmology, where physical quantities are expanded as a Taylor series in the cosmological redshift, or in related variables. Here we apply this methodology to…

Cosmology and Nongalactic Astrophysics · Physics 2022-03-08 C. J. A. P. Martins , F. P. S. A. Ferreira , P. V. Marto

Recent results from a number of redshift surveys suggest that the Universe is well described by an inhomogeneous, fractal distribution on the largest scales probed. This distribution has been found to have fractal dimension, D,…

Astrophysics · Physics 2009-10-31 S. J. Hatton

We present a new model universe based on the junction of FRW to flat Lemaitre-Tolman-Bondi (LTB) solutions of Einstein equations along our past light cone, bringing structures within the FRW models. The model is assumed globally to be…

Astrophysics · Physics 2008-11-26 Sh. Khosravi , E. Kourkchi , R. Mansouri , Y. Akrami

Usually, we assume that there is no inhomogeneity isotropic in terms of our location in our uni- verse. This assumption has not been observationally confirmed yet in sufficient accuracy, and we need to consider the possibility that there…

Cosmology and Nongalactic Astrophysics · Physics 2017-03-06 Hiroyuki Negishi , Ken-ichi Nakao

Answering an informal question of K. Park, we show that by fixing some irrational alpha to have a particular standard continued fraction expansion, we may force the associated discrepancy sequences for all x in [0,1), which track the…

Number Theory · Mathematics 2011-06-06 David Ralston

We examine the recently derived quantum-mechanical relation between atomic polarizabilities and equilibrium internuclear distances in van der Waals (vdW) bonded diatomic systems [Phys. Rev. Lett. {\bf 121}, 183401 (2018)]. For homonuclear…

Chemical Physics · Physics 2020-07-08 Alexandre Tkatchenko , Dmitry V. Fedorov

We produce the simple formula for the radius R of a cold body of mass M, (4 pi rho/3)^{1/3} R = I.M^{1/3} / [1+ (M/Mp)^{2/3}], where I is one for white dwarfs with non-relativistic electrons, but depends on the ratio of the total mass to…

Astrophysics · Physics 2007-05-23 D. Lynden-Bell , J. P. O'Dwyer

In this paper we prove convergence results for the homogenization of the Dirichlet problem with rapidly oscillating boundary data in convex polygonal domains. Our analysis is based on integral representation of solutions. Under a certain…

Analysis of PDEs · Mathematics 2015-06-16 Hayk Aleksanyan , Henrik Shahgholian , Per Sjölin

It is well known that alternative theories to the Standard Model allow -- and sometimes require -- fundamental constants, such as the fine-structure constant, $\alpha$, to vary in spacetime. We demonstrate that one way to investigate these…

High Energy Physics - Phenomenology · Physics 2025-03-17 E. -A. Kolonia , C. J. A. P. Martins , Konstantinos N. Gourgouliatos

We study the Erd\H os-Falconer distance problem for a set $A\subset \mathbb{F}^2$, where $\mathbb{F}$ is a field of positive characteristic $p$. If $\mathbb{F}=\mathbb{F}_p$ and the cardinality $|A|$ exceeds $p^{5/4}$, we prove that $A$…

Combinatorics · Mathematics 2022-05-05 Brendan Murphy , Giorgis Petridis , Thang Pham , Misha Rudnev , Sophie Stevens

We introduce the notion of the $\alpha$-Haagerup approximation property for $\alpha\in[0,1/2]$ using a one-parameter family of positive cones studied by Araki and show that the $\alpha$-Haagerup approximation property actually does not…

Operator Algebras · Mathematics 2014-10-23 Rui Okayasu , Reiji Tomatsu

Most cosmological models studied today are based on the assumption of homogeneity and isotropy. Observationally one can find evidence that supports these assumptions on very large scales, the strongest being the almost isotropy of the…

Astrophysics · Physics 2007-05-23 Christian Sicka , Thomas Buchert , Martin Kerscher

Let $\mathbb D$ be the unit disc in $\mathbb C$ and let $f:\mathbb D \to \mathbb C$ be a Riemann map, $\Delta=f(\mathbb D)$. We give a necessary and sufficient condition in terms of hyperbolic distance and horocycles which assures that a…

Complex Variables · Mathematics 2018-06-19 Filippo Bracci , Manuel D. Contreras , Santiago Díaz-Madrigal , Hervé Gaussier

Let $p$ be a real number greater than one and let $X$ be a locally compact, noncompact metric measure space that satisfies certain conditions. The $p$-Royden and $p$-harmonic boundaries of $X$ are constructed by using the $p$-Royden algebra…

Metric Geometry · Mathematics 2015-06-09 Marcello Lucia , Michael Puls

The work is motivated by the Faraday cage effect. We consider the Helmholtz equation over a 3D-domain containing a thin heterogeneous interface of thickness $\delta \ll 1$. The layer has a $\delta-$periodic structure in the in-plane…

Analysis of PDEs · Mathematics 2022-12-12 S Aiyappan , Georges Griso , Julia Orlik

Based on the Lema\^itre-Tolman-Bondi (LTB) metric we consider two flat inhomogeneous big-bang models. We aim at clarifying, as far as possible analytically, basic features of the dynamics of the simplest inhomogeneous models and to point…

General Relativity and Quantum Cosmology · Physics 2016-05-25 Eddy G. Chirinos Isidro , Cristofher Zuñiga Vargas , Winfried Zimdahl

In the multi-fractal analysis of large scale matter distribution, the scale of transition to homogeneity is defined as the scale above which the fractal dimension of underlying point distribution is equal to the ambient dimension of the…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-13 Jaswant K. Yadav , J. S. Bagla , Nishikanta Khandai

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
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