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Related papers: Varying Fine-Structure Constant and the Cosmologic…

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The data from the QSO absorption lines indicating a nonzero time-variability of the fine-structure constant has been re-analyzed on the basis of a "damped-oscillator" fit, as motivated by the same type of behavior of a scalar field,…

Astrophysics · Physics 2015-06-24 Yasunori Fujii

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

Theoretical background of our proposed relation between the accelerating universe and the time-variability of the fine-structure constant is discussed, based on the scalar-tensor theory, with emphases on the intuitive aspects of underlying…

Cosmology and Nongalactic Astrophysics · Physics 2009-10-28 Yasunori Fujii

Recent theoretical ideas and observational claims suggest that the fine structure constant alpha may be variable. We examine a spectrum of models in which alpha is a function of a scalar field. Specifically, we consider three scenarios:…

High Energy Physics - Phenomenology · Physics 2009-11-10 Charles L. Steinhardt

In 1976, Shlyakhter showed that the Sm data from Oklo results in the upper bound on the time-variability of the fine-structure constant: $|\dot{\alpha}/\alpha| \lsim 10^{-17}{\rm y}^{-1}$, which has ever been the most stringent bound. Since…

Astrophysics · Physics 2009-11-07 Yasunori Fujii

Endeavours of the unification of the four fundamental interactions have resulted in a development of theories having cosmological solutions in which low-energy limits of fundamental physical constants vary with time. The validity of such…

Astrophysics · Physics 2011-05-23 A. V. Ivanchik , A. Y. Potekhin , D. A. Varshalovich

We present a theoretical calculation on the time-variability of the fine-structure constant to fit the result of the recent precise analysis of the measurement of the QSO absorption lines. We find the parameters and initial values of the…

Astrophysics · Physics 2008-11-26 Yasunori Fujii

Fundamental constants are a cornerstone of our physical laws. Any constant varying in space and/or time would reflect the existence of an almost massless field that couples to matter. This will induce a violation of the universality of free…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 Jean-Philippe Uzan

The Oklo phenomenon, natural fission reactors which had taken place in Gabon about 2 billion years ago, provides one of the most stringent constraints on the possible time-variability of the fine-structure constant $\alpha$. We first review…

High Energy Physics - Phenomenology · Physics 2017-08-23 Yasunori Fujii

If the reported measurements of the time variation of the fine structure constant from observations of distant QSOs are correct, combined with the Oklo limit they would strongly constrain the class of the quintessence potential. If these…

High Energy Physics - Phenomenology · Physics 2009-11-07 Takeshi Chiba , Kazunori Kohri

We work with a class of scalar extended theory of gravity that can drive the present cosmic acceleration as well as accommodate a mild cosmic variation of the fine structure constant $\alpha$. The motivation comes from a vintage theory…

General Relativity and Quantum Cosmology · Physics 2022-04-20 Soumya Chakrabarti

An attempt is made for a new type of analysis of the time-variability of the fine-structure constant trying to fit the most recent result from the laboratory measurements, the Oklo constraint and the data from the QSO absorption lines all…

Astrophysics · Physics 2009-12-04 Yasunori Fujii

We show how the scalar field, a candidate of quintessence, in a proposed model of the scalar-tensor theories of gravity provides a way to understand a small but nonzero cosmological constant as indicated by recent observations. A particular…

General Relativity and Quantum Cosmology · Physics 2009-09-25 Yasunori Fujii

There are indications from the study of quasar absorption spectra that the fine structure constant $\alpha$ may have been measurably smaller for redshifts $z>2.$ Analyses of other data ($^{149}$Sm fission rate for the Oklo natural reactor,…

High Energy Physics - Phenomenology · Physics 2009-11-10 Luis Anchordoqui , Haim Goldberg

The accelerating universe is closely related to today's version of the cosmological constant problem; fine-tuning and coincidence problems. We show how successfully the scalar-tensor theory, a rather rigid theoretical idea, provides us with…

Cosmology and Nongalactic Astrophysics · Physics 2009-09-01 Yasunori Fujii

Temporal and spatial variation of fine-structure constant $\alpha\equiv e^2/\hbar c$ in cosmology has been reported in analysis of combination Keck and VLT data. This paper studies this variation based on consideration of basic spacetime…

General Relativity and Quantum Cosmology · Physics 2015-09-02 Sze-Shiang Feng , Mu-Lin Yan

We explore the possibility that the reported time variation of the fine structure constant $\alpha$ is due to a coupling between electromagnetism and gravitation. This may reconcile the claimed results on $\alpha$ with the upper limit from…

General Relativity and Quantum Cosmology · Physics 2011-05-23 J. P. Mbelek , M. Lachièze-Rey

We study the change of the effective fine structure constant in the cosmological models of a scalar field with a non-vanishing coupling to the electromagnetic field. Combining cosmological data and terrestrial observations we place…

High Energy Physics - Phenomenology · Physics 2009-11-10 E. J. Copeland , N. J. Nunes , M. Pospelov

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

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
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