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Related papers: Testing the Stability of the Fine Structure Consta…

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[O III]$\lambda\lambda$4960,5008 doublet are often the strongest narrow emission lines in starburst galaxies and quasi-stellar objects (QSOs), and thus are a promising probe to possible variation of the fine-structure constant $\alpha$ over…

Astrophysics of Galaxies · Physics 2023-10-30 Ge Li , Luming Sun , Xiangjun Chen , Hongyan Zhou

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

Recent advances in spectroscopic instrumentation and calibration methods dramatically improve the quality of quasar spectra. Supercomputer calculations show that, at high spectral resolution, procedures used in some previous analyses of…

Cosmology and Nongalactic Astrophysics · Physics 2022-03-15 John K. Webb , Chung-Chi Lee , Dinko Milaković

We study a theory in which the electromagnetic field is disformally coupled to a scalar field, in addition to a usual non-minimal electromagnetic coupling. We show that disformal couplings modify the expression for the fine-structure…

Cosmology and Nongalactic Astrophysics · Physics 2015-12-16 Carsten van de Bruck , Jurgen Mifsud , Nelson J. Nunes

Discussion of the constancy, or otherwise, of the various so-called universal constants which abound in physics has continued for many years. However, relatively recent observations, which appear to indicate a variation in the value of the…

General Physics · Physics 2007-08-21 A. D. Law , J. Dunning-Davies

At present several groups are analyzing astrophysical data in a search for time-variation of the fine structure constant $\alpha$. Here we discuss how to exclude systematic effects caused by the changes in the isotope abundances during the…

Astrophysics · Physics 2009-08-18 M. G. Kozlov , V. A. Korol , J. C. Berengut , V. A. Dzuba , V. V. Flambaum

We investigate the triple-alpha process and the Oklo phenomenon to obtain constraints on possible cosmological time variations of fundamental constants. Specifically we study cosmological temporal constraints for the fine structure constant…

Astrophysics · Physics 2009-11-07 H. Oberhummer , A. Csoto , M. Fairbairn , H. Schlattl , M. M. Sharma

If the fine structure constant $\alpha =e^2/(\hbar c)$ were to change, then a number of interpretations would be possible, attributing this change either to variations in the electron charge, the dielectric constant of the vacuum, the speed…

Astrophysics · Physics 2009-10-31 John D. Barrow , Joao Magueijo

By analyzing the survival probability amplitude of an unstable state we show that the energy corrections to this state in the long ($t \to \infty$) and relatively short (lifetime of the state) time regions, are different. It is shown that…

High Energy Physics - Phenomenology · Physics 2008-12-18 K. Urbanowski

We set up a framework for a model-independent analysis of the time variation of $e$, $\hbar$, and $c$ indiviually. It is shown that the time-evolution of each constant can be determined uniquely from the time evolution of the fine structure…

High Energy Physics - Phenomenology · Physics 2009-11-10 A. Yu. Ignatiev , B. J. Carson

The sensitivity parameter is widely used for quantifying fine tuning. However, examples show it fails to give correct results under certain circumstances. We argue that the problems of the sensitivity parameter are almost identical to the…

High Energy Physics - Phenomenology · Physics 2009-02-05 Su Yan

The ever increasing complexity of real-time control systems results in significant deviations in the timing of sensing and actuation, which may lead to degraded performance or even instability. In this paper we present a method to analyze…

Systems and Control · Electrical Eng. & Systems 2020-04-27 Maximilian Gaukler , Günter Roppenecker , Peter Ulbrich

Contemporary multidimensional cosmological theories predict different variations of fundamental physical constants in course of the cosmological evolution. On the basis of the QSO spectra analysis, we show that the fine-structure constant…

Astrophysics · Physics 2007-05-23 D. A. Varshalovich , A. Y. Potekhin , A. V. Ivanchik , V. E. Panchuk , K. M. Lanzetta

The progress of Particle Physics is closely linked to the progress in the understanding of the fundamental constants, like the finestructure constant, the mass of the electron or nucleon, or the electroweak mixing angle. The relation…

High Energy Physics - Phenomenology · Physics 2015-06-25 H. Fritzsch

We review some of the history and properties of theories for the variation of the gravitation and fine structure 'constants'. We highlight some general features of the cosmological models that exist in these theories with reference to…

General Relativity and Quantum Cosmology · Physics 2014-11-17 John D. Barrow

A phenomenological model is proposed to explain the recent observed cosmological variation of the fine structure constant as an effect of the quantum vacuum, assuming a flat universe with cosmological constant $\Lambda$ in the cases…

Astrophysics · Physics 2010-12-17 Antonio F. Rañada

We introduce a model which allows the fine structure constant (alpha) to vary throughout space and time due to a coupling to a scalar field with a non-canonical kinetic structure. This provided a new extension of the…

General Relativity and Quantum Cosmology · Physics 2015-01-20 Alexander A. H. Graham

In the present report the author presents a simple and systematically defined formula for the fine structure constant based only on the number $\pi$. The difference between the suggested value and the currently known experimental one is…

General Physics · Physics 2007-05-23 Anastass Anastasov

A summary is given of the current status of measurements of the strong coupling constant $\alpha_s$ performed at LEP. These include measurements from inclusive observables as well as from event shape variables. Recent results based on power…

High Energy Physics - Experiment · Physics 2007-05-23 G. Dissertori

A brief review of the search for variation of the fine structure constant in quasar absorption spectra is presented. Special consideration is given to the role of atomic calculations in the analysis of the observed data. A range of methods…

Atomic Physics · Physics 2015-05-13 V. A. Dzuba , V. V. Flambaum