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There are some theoretical arguments about possible variations of fundamental constants with cosmic time. We review the fact that all conversion factors depend on these quantities and consider how their variations may affect transformations…

General Relativity and Quantum Cosmology · Physics 2020-12-29 Yousef Bisabr

We perform calculations of the dependence of nuclear magnetic moments on quark masses and obtain limits on the variation of the ratio of quark mass and strong interaction scale (m_q/Lambda_{QCD}) from recent atomic clock experiments with…

Atomic Physics · Physics 2016-09-08 V. V. Flambaum

Within the context of mass-varying neutrinos, we construct a cosmological model that has a phase transition in the electromagnetic fine structure constant \alpha at a redshift of 0.5. The model accommodates hints of a time variable \alpha…

High Energy Physics - Phenomenology · Physics 2008-11-26 L. Anchordoqui , V. Barger , H. Goldberg , D. Marfatia

Space-time variation of fundamental physical constants in expanding Universe is predicted by a number of popular models. The masses of second generation quarks are larger than first generation quark masses by several orders of magnitude,…

High Energy Physics - Phenomenology · Physics 2023-01-18 V. V. Flambaum , P. Munro-Laylim

Calculation of the Dirac hydrogen atom spectrum in the framework of dynamical fine structure constant (alpha) variability discloses a small departure in the laboratory from Sommerfeld's formula for the fine structure shifts, possibly…

Astrophysics · Physics 2007-05-23 Jacob D. Bekenstein

The Cosmic Microwave Background anisotropies provide a unique opportunity to constrain simultaneous variations of the fine-structure constant $\alpha$ and Newton's gravitational constant $G$. Those correlated variations are possible in a…

Cosmology and Nongalactic Astrophysics · Physics 2010-10-28 C. J. A. P. Martins , Eloisa Menegoni , Silvia Galli , Gianpiero Mangano , Alessandro Melchiorri

We perform calculations of the dependence of nuclear magnetic moments on quark masses and obtain limits on the variation of $(m_q/\Lambda_{QCD})$ from recent measurements of hydrogen hyperfine (21 cm) and molecular rotational transitions in…

High Energy Physics - Phenomenology · Physics 2009-08-18 V. V. Flambaum , D. B. Leinweber , A. W. Thomas , R. D. Young

We discuss how existing astrophysical measurements of various combinations of the fine-structure constant $\alpha$, the proton-to-electron mass ratio $\mu$ and the proton gyromagnetic ratio g$_{p}$ towards the radio source PKS1413+135 can…

Cosmology and Nongalactic Astrophysics · Physics 2013-10-01 A. M. R. V. L. Monteiro , M. C. Ferreira , M. D. Julião , C. J. A. P. Martins

We review 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 recent quasar data that are…

Astrophysics · Physics 2009-11-13 John D. Barrow

We show that it is possible to steer clear of a spacetime singularity during gravitational collapse by considering the time-variation of a fundamental coupling, in this case, the fine structure constant {\alpha}. We study a spherical…

General Relativity and Quantum Cosmology · Physics 2023-08-08 Soumya Chakrabarti

We reanalyze Oklo $^{149}$Sm data using realistic models of the natural nuclear reactors. Disagreements among recent Oklo determinations of the time evolution of $\alpha$, the electromagnetic fine structure constant, are shown to be due to…

Nuclear Experiment · Physics 2008-11-26 C. R. Gould , E. I. Sharapov , S. K. Lamoreaux

We study constraints on time variation of the fine structure constant alpha from cosmic microwave background (CMB) taking into account simultaneous change in alpha and the electron mass m_e which might be implied in unification theories. We…

Astrophysics · Physics 2008-11-26 Kazuhide Ichikawa , Toru Kanzaki , Masahiro Kawasaki

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

Time variation of fundamental constants would not be surprising in the framework of theories involving extra dimensions. The variation of any one constant is likely to be correlated with variations of others in a pattern that is diagnostic…

High Energy Physics - Phenomenology · Physics 2014-11-17 Paul Langacker

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

A possibility for fundamental constants to vary in time is suggested by theories unifying gravity with other interactions. In this article we examine proposals to use optical transitions of Sr, Dy, YbII and YbIII for the search of the time…

Atomic Physics · Physics 2009-02-05 V. A. Dzuba , V. V. Flambaum , M. V. Marchenko.

[NOTE: This 1983 preprint is being uploaded to arXiv.org after the death of its author, who supported online distribution of his work. Contact info of the submitter is at http://ilya.cc .] The positions of neutron resonances have been shown…

General Physics · Physics 2007-05-23 Alexander I. Shlyakhter

We discuss limits on variation of $(m_q/\Lambda_{QCD})$. The results are obtained by studying $n-\alpha$-interaction during Big Bang, Oklo natural nuclear reactor data and limits on variation of the proton $g$-factor from quasar absorpion…

Astrophysics · Physics 2009-08-18 V. F. Dmitriev , V. V. Flambaum

We consider astronomical and local bounds on time variation of fundamental constants to test some generic Kaluza-Klein-like models and some particular cases of Beckenstein theory. Bounds on the free parameters of the different theories are…

Astrophysics · Physics 2009-10-31 Susana J. Landau , Hector Vucetich

The current observational and experimental bounds on the time variation of the constants of nature (the fine structure constant $\alpha$, the gravitational constant $G$ and the proton-electron mass ratio $\mu=m_p/m_e$) are reviewed.

General Relativity and Quantum Cosmology · Physics 2012-01-03 Takeshi Chiba
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