English
Related papers

Related papers: Determination of the Fine Structure Constant by $\…

200 papers

Astrophysical tests of the stability of dimensionless fundamental couplings, such as the fine-structure constant $\alpha$, are an area of much increased recent activity, following some indications of possible spacetime variations at the few…

Cosmology and Nongalactic Astrophysics · Physics 2014-07-16 P. M. M. Leal , C. J. A. P. Martins , L. B. Ventura

Accurate predictions of hyperfine structure (HFS) constants are important in many areas of chemistry and physics, from the determination of nuclear electric and magnetic moments to benchmarking of new theoretical methods. We present a…

Atomic Physics · Physics 2020-07-01 Pi A. B. Haase , Ephraim Eliav , Miroslav Iliaš , Anastasia Borschevsky

The fine-structure constant {\alpha}, the dimensionless number that represents the strength of electromagnetic coupling in the limit of sufficiently low energy interactions, is the crucial fundamental physical parameter that governs a…

General Physics · Physics 2012-02-14 Charles Kirkham Rhodes

We test the prediction of the time variation of the fine structure constant in the string dilaton model proposed by Damour and Polyakov. First, we analize the dependence of all available observational and experimental data with the fine…

Astrophysics · Physics 2007-05-23 Susana J. Landau , Melina Bersten , Pablo Sisterna , Hector Vucetich

This letter explores how a reinterpretation of the generalized uncertainty principle as an effective variation of Planck's constant provides a physical explanation for a number of fundamental quantities and couplings. In this context, a…

General Physics · Physics 2024-09-02 Ahmed Farag Ali , Jonas Mureika , Elias C. Vagenas , Ibrahim Elmashad

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

The fine structure constant $\alpha$ has a particular status in physics. Its precise determination is required to test the quantum electrodynamics (QED) theory. The constant $\alpha$ is also a keystone for the determination of other…

It is possible that fundamental constants may not be constant at all. There is a generally accepted view that one can only talk about variations of dimensionless quantities, such as the fine structure constant $\alpha_{\rm e}\equiv…

Cosmology and Nongalactic Astrophysics · Physics 2011-01-27 Adam Moss , Ali Narimani , Douglas Scott

We report a new constraint on the variation of the fine-structure constant based on the analysis of 15 Si IV doublets selected from a ESO-UVES sample. We find \Delta\alpha/\alpha = (+0.15+/-0.43) x 10^-5 over a redshift range of 1.59< z <…

Astrophysics · Physics 2009-11-10 Hum Chand , Patrick Petitjean , Raghunathan Srianand , Bastien Aracil

Gini index is a widely used measure of economic inequality. This article develops a general theory for constructing a confidence interval for Gini index with a specified confidence coefficient and a specified width. Fixed sample size…

Methodology · Statistics 2017-09-21 Bhargab Chattopadhyay , Shyamal Krishna De

We describe the results of a search for time variability of the fine structure constant, alpha, using absorption systems in the spectra of distant quasars. Three large optical datasets and two 21cm/mm absorption systems provide four…

Fundamental mathematical constants like $e$ and $\pi$ are ubiquitous in diverse fields of science, from abstract mathematics to physics, biology and chemistry. For centuries, new formulas relating fundamental constants have been scarce and…

Machine Learning · Computer Science 2021-04-29 Gal Raayoni , Shahar Gottlieb , George Pisha , Yoav Harris , Yahel Manor , Uri Mendlovic , Doron Haviv , Yaron Hadad , Ido Kaminer

The comparison of different atomic transition frequencies over time can be used to determine the present value of the temporal derivative of the fine structure constant alpha in a model-independent way without assumptions on constancy or…

Atomic Physics · Physics 2009-11-10 E. Peik , B. Lipphardt , H. Schnatz , T. Schneider , Chr. Tamm , S. G. Karshenboim

We consider several transitions between narrow lines that have an enhanced sensitivity to a possible variation of the fine structure constant, alpha. This enhancement may allow a search to be performed with an effective suppression of the…

Atomic Physics · Physics 2009-11-11 S. G. Karshenboim , A. Yu. Nevsky , E. J. Angstmann , V. A. Dzuba , V. V. Flambaum

I briefly present some current theoretical motivations for time or space variations of the fundamental constants of nature and review current key observational results. I focus on the fine-structure constant, and particularly on…

Astrophysics · Physics 2007-05-23 C. J. A. P. Martins

Searches for variations of fundamental constants require accurate measurement errors. There are several potential sources of errors and quantifying each one accurately is essential. This paper addresses one source of uncertainty relating to…

Instrumentation and Methods for Astrophysics · Physics 2022-12-02 Chung-Chi Lee , John K. Webb , Darren Dougan , Vladimir A. Dzuba , Victor V. Flambaum

We determine a cosmological model that include a positive acceleration of the Universe and a time decreasing fine structure constant. The present day deceleration parameter is estimated by us, according to our model and the available…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Marcelo S. Berman , Luis A. Trevisan

In this short note, using notions from $p$-Adic QFT and $p$-branes, we derive the transfinite M $theoretical$ corrections $(\alpha_M)^{-1} = 100 + 61 \phi$ to El Naschie's inverse fine structure constant value $(\alpha_{HS})^{-1}= 100 +…

General Physics · Physics 2015-06-26 Carlos Castro

Dependence of transition frequencies on the fine structure constant $\alpha=e^2/\hbar c$ is calculated for several many-electron systems which are used or planned to be used in the laboratory search for the time variation of the fine…

Atomic Physics · Physics 2009-11-13 V. A. Dzuba , V. V. Flambaum

This article describes the various experimental bounds on the variation of the fundamental constants of nature. After a discussion on the role of fundamental constants, of their definition and link with metrology, the various constraints on…

High Energy Physics - Phenomenology · Physics 2008-11-26 Jean-Philippe Uzan