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We analyze the consistency of different astronomical data of the variation in the fine-structure constant obtained with KECK and VLT. We tested the consistency using the Student test and confidence intervals. We splited the data sets in to…

Cosmology and Nongalactic Astrophysics · Physics 2013-08-27 Lucila Kraiselburd , Susana J. Landau , Claudio Simeone

A brief description of the main methods for determining the fine structure constant is given. It is shown that the exact value of the fine structure constant is important for the new International System of Units (SI) and for fundamental…

High Energy Physics - Phenomenology · Physics 2025-06-24 K. A. Bronnikov , V. D. Ivashchuk , V. V. Khruschov

A new method for examining the possible space-time variation of the fine structure constant ($\alpha$) is proposed. The technique uses a relatively simple measurement with an optical resonator to compare atom-stabilized optical frequency…

Atomic Physics · Physics 2007-05-23 J. R. Torgerson

We derive formulae for the time variation of the gravitational ``constant'' and of the fine structure ``constant'' in various models with extra dimensions and analyze their consistency with the observational data.

General Relativity and Quantum Cosmology · Physics 2007-05-23 E. Garcia-Berro , Yu. A. Kubyshin , P. Loren-Aguilar

We review recent activity searching for variations in the fundamental constants of nature in quasar absorption spectra and in the laboratory. While research in this direction has been ongoing for many decades, the topic has recently been…

Atomic Physics · Physics 2011-02-02 J. C. Berengut , V. V. Flambaum

In this review we discuss the progress of the past decade in testing for a possible temporal variation of the fine structure constant $\alpha$. Advances in atomic sample preparation, laser spectroscopy and optical frequency measurements led…

Quantum Physics · Physics 2015-05-13 N. Kolachevsky , A. Matveev , J. Alnis , C. Parthey , T. Steinmetz , T. Wilken , R. Holzwarth , Th. Udem , T. W. Haensch

Much work has been done after the possibility of a fine structure constant being time-varying. It has been taken as an indication of a time-varying speed of light. Here we prove that this is not the case. We prove that the speed of light…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Antonio Alfonso-Faus

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

We briefly review the recent experimental results on possible variations of the fine structure constant $\alpha$ on the cosmological time scale and its position dependence. We outline the theoretical grounds for the assumption that $\alpha$…

General Relativity and Quantum Cosmology · Physics 2012-05-11 K. A. Bronnikov , S. A. Kononogov

Determination of the fine structure constant alpha and search for its possible variation are considered. We focus on a role of the fine structure constant in modern physics and discuss precision tests of quantum electrodynamics. Different…

Atomic Physics · Physics 2015-06-26 Savely G. Karshenboim

We search for transient variations of the fine structure constant using data from a European network of fiber-linked optical atomic clocks. By searching for coherent variations in the recorded clock frequency comparisons across the network,…

We consider an application of precision frequency measurements to searches for possible time variations of the fundamental physical constants. Current laboratory constraints on variations of the fine structure constant alpha and other…

Atomic Physics · Physics 2007-05-23 Savely G. Karshenboim , Victor Flambaum , Ekkehard Peik

We calculate the fine structure constant in the spacetime of a cosmic string. In the presence of a cosmic string the value of the fine structure constant reduces. We also discuss on numerical results.

High Energy Physics - Theory · Physics 2009-11-11 Forough Nasseri

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

A method offering an order of magnitude sensitivity gain is described for using quasar spectra to investigate possible time or space variation in the fine structure constant, alpha. Applying the technique to a sample of 30 absorption…

We review the observational information on the constancy of the fine structure constant alpha. We find that small improvements on the measurement of ^{187}Re lifetime can provide significant progress in exploring the range of variability…

Astrophysics · Physics 2009-11-07 G. Fiorentini , B. Ricci

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

We discuss the fundamemtal constants in the Standard Model of particle physics, in particular possible changes of these constants on the cosmological time scale. The Grand Unification of the observed strong, electromagnetic and weak…

High Energy Physics - Phenomenology · Physics 2016-10-25 Harald Fritzsch

The problem of detecting variance breaks in the case of smooth time-varying variance structure is studied. It is highlighted that the tests based on (piecewise) constant specification of the variance are not able to distinguish between…

Methodology · Statistics 2017-07-24 Ben Hajria Raja , Khardani Salah , Raïssi Hamdi

In astronomy, there is an opportunity to enhance the practice of validating models through statistical techniques, specifically to account for measurement error uncertainties. While models are commonly used to describe observations, there…

Instrumentation and Methods for Astrophysics · Physics 2023-08-09 Fiorenzo Stoppa , Eric Cator , Gijs Nelemans
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