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We study dependence of the CMB temperature anisotropy spectrum on the value of the fine structure constant $\alpha$ and the equation of state of the dark energy component of the total density of the universe. We find that bounds imposed on…

Astrophysics · Physics 2014-10-13 Greg Huey , Stephon Alexander , Levon Pogosian

Recent progress in studying the physics of amorphous solids has revealed that mechanical strains can be strongly screened by the formation of plastic events that are typically quadrupolar in nature. The theory stipulated that gradients in…

Disordered Systems and Neural Networks · Physics 2021-11-23 Bhanu Prasad Bhowmik , Michael Moshe , Itamar Procaccia

We consider the density wave instability of fermionic dipoles aligned by an external field, and moving in equidistant layers at zero temperature. Using a conserving Hartree-Fock approximation, we show that correlations between dipoles in…

Quantum Gases · Physics 2012-10-05 J. K. Block , N. T. Zinner , G. M. Bruun

We use the strong nebular lines of O III, 5007 A and 4959 A, to set a robust upper limit on the time dependence of the fine structure constant. We find |alpha^{-1} d alpha(t)/dt | < 2*10^{-13} yr, corresponding to Delta alpha/alpha(0) =…

Astrophysics · Physics 2009-09-29 John N. Bahcall , Charles L. Steinhardt , David Schlegel

In a recent publication [Ferreira {\it et al.}, Phys. Rev. D89 (2014) 083011] we tested the consistency of current astrophysical tests of the stability of the fine-structure constant $\alpha$ and the proton-to-electron mass ratio…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 M. C. Ferreira , C. J. A. P. Martins

We study the $\Lambda(\alpha)$CDM models with $\Lambda(\alpha)$ being a function of the time-varying fine structure constant $\alpha$. We give a close look at the constraints on two specific $\Lambda(\alpha)$CDM models with one and two…

Cosmology and Nongalactic Astrophysics · Physics 2018-09-13 Jin-Jun Zhang , Lu Yin , Chao-Qiang Geng

Bekenstein's model of a scalar field, \phi, that affects the electromagnetic permeability (usually identified with ``changing \alpha'') predicts tiny variations of the effective fine structure constant up to very high red-shifts,…

High Energy Physics - Phenomenology · Physics 2009-09-15 Keith A. Olive , Maxim Pospelov

Low amplitude (linear regime) cosmic density fluctuations lead to spatial variations in the locally measurable value of $H_0$ (denoted as $H_L$), $\delta_H \equiv (H_L-H_0)/H_0$, which are of order 3-6% (95% confidence interval) in a sphere…

Astrophysics · Physics 2009-10-30 Yun Wang , David N. Spergel , Edwin L. Turner

Astrophysical tests of the stability of dimensionless fundamental couplings, such as the fine-structure constant $\alpha$ and the proton-to-electron mass ratio $\mu$, are an optimal probe of new physics. There is a growing interest in these…

Cosmology and Nongalactic Astrophysics · Physics 2016-07-07 A. C. O. Leite , C. J. A. P. Martins

A significant tension has become manifest between the current expansion rate of our Universe measured from the cosmic microwave background by the Planck satellite and from local distance probes, which has prompted for interpretations of…

Cosmology and Nongalactic Astrophysics · Physics 2020-02-27 Lucas Lombriser

In order to investigate the origin of the ongoing tension between the amplitude of matter fluctuations measured by weak lensing experiments at low redshifts and the value inferred from the cosmic microwave background anisotropies, we…

We propose an extrapolation technique that allows accuracy improvement of the discrete dipole approximation computations. The performance of this technique was studied empirically based on extensive simulations for 5 test cases using many…

Optics · Physics 2008-07-29 Maxim A. Yurkin , Valeri P. Maltsev , Alfons G. Hoekstra

We perform a comprehensive redshift-space distortion analysis based on cosmic voids in the large-scale distribution of galaxies observed with the Sloan Digital Sky Survey. To this end, we measure multipoles of the void-galaxy…

Cosmology and Nongalactic Astrophysics · Physics 2017-07-12 Nico Hamaus , Marie-Claude Cousinou , Alice Pisani , Marie Aubert , Stéphanie Escoffier , Jochen Weller

In limited data computerized tomography, the 2D or 3D problem can be reduced to a family of 1D problems using the differentiated backprojection (DBP) method. Each 1D problem consists of recovering a compactly supported function $f \in…

Classical Analysis and ODEs · Mathematics 2016-05-25 Rima Alaifari , Michel Defrise , Alexander Katsevich

Recently it was pointed out that transition frequencies in certain diatomic molecules have an enhanced sensitivity to variations in the fine-structure constant $\alpha$ and the proton-to-electron mass ratio $m_p/m_e$ due to a near…

Atomic Physics · Physics 2010-08-31 K. Beloy , A. Borschevsky , P. Schwerdtfeger , V. V. Flambaum

The connection between the dipolar modulation asymmetry and the quadrupole-octopole alignment in the CMB is studied in this work. First, a generalization of the dipolar modulation model is proposed by considering that the amplitude may…

Cosmology and Nongalactic Astrophysics · Physics 2019-11-06 A. Marcos-Caballero , E. Martínez-González

Dipole moments are a simple, global measure of the accuracy of the electron density of a polar molecule. Dipole moments also affect the interactions of a molecule with other molecules as well as electric fields. To directly assess the…

Chemical Physics · Physics 2018-04-11 Diptarka Hait , Martin Head-Gordon

We characterize the radial and angular variance of the Hubble flow in the COMPOSITE sample of 4534 galaxies, on scales in which much of the flow is in the nonlinear regime. With no cosmological assumptions other than the existence of a…

Cosmology and Nongalactic Astrophysics · Physics 2013-10-30 David L. Wiltshire , Peter R. Smale , Teppo Mattsson , Richard Watkins

We report on constraints to the cosmological jerk parameter ($j$) and to possible variability of the fine-structure constant ($\Delta \alpha/\alpha$) based on stochastic quintessence models of dark energy, discussed by Chongchitnan and…

Cosmology and Nongalactic Astrophysics · Physics 2016-03-23 Christine C. Dantas , Andre L. B. Ribeiro

Astrophysical tests of the stability of fundamental couplings, such as the fine-structure constant $\alpha$, are becoming an increasingly powerful probe of new physics. Here we discuss how these measurements, combined with local atomic…

Cosmology and Nongalactic Astrophysics · Physics 2015-09-09 C. J. A. P. Martins , A. M. M. Pinho , R. F. C. Alves , M. Pino , C. I. S. A. Rocha , M. von Wietersheim