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Related papers: Time-Varying alpha and Particle Physics

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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

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

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

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

It has been widely believed that variability of the fine-structure constant alpha would imply detectable violations of the weak equivalence principle. This belief is not justified in general. It is put to rest here in the context of the…

General Relativity and Quantum Cosmology · Physics 2009-11-07 Jacob D. Bekenstein

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 experimental data indicates that the fine structure constant alpha may be varying on cosmological time scales. We consider the possibility that such a variation could be induced by a second order phase transition which occurs at late…

High Energy Physics - Phenomenology · Physics 2010-04-05 Z. Chacko , C. Grojean , M. Perelstein

We start with a brief account of the latest analysis of the Oklo phenomenon providing the still most stringent constraint on time-variability of the fine- structure constant $\alpha$. Comparing this with the recent result from the…

General Relativity and Quantum Cosmology · Physics 2009-11-07 Yasunori Fujii

We consider a long range scalar force that mainly couples to dark matter and unstable Standard Model states, like the muon, with tiny strength. Probing this type of force would present a challenge to observations. We point out that the…

High Energy Physics - Phenomenology · Physics 2018-12-13 Hooman Davoudiasl , Pier Paolo Giardino

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

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

Astrophysical observations suggest that the fine structure constant (alpha) may (or may not) be evolving over the cosmological time scale. This raises a much debated question: is alpha variation due to the variation of the speed of light…

High Energy Physics - Phenomenology · Physics 2007-05-23 A. Yu. Ignatiev , B. J. Carson

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 present a class of models in which the coupling of the photon to an ultralight scalar field that has a time-dependent vacuum expectation value causes the fine structure constant to oscillate in time. The scalar field is assumed to…

High Energy Physics - Phenomenology · Physics 2022-09-07 Dawid Brzeminski , Zackaria Chacko , Abhish Dev , Anson Hook

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

We study inhomogeneous cosmological variations in the fine structure 'constant', $\alpha ,$ in Friedmann universes. Inhomogeneous motions of the scalar field driving changes in $\alpha $ display spatial oscillations that decrease in…

Astrophysics · Physics 2009-11-07 J. D. Barrow , J. Magueijo , H. B. Sandvik

We review properties of cosmological theories for the variation of the fine structure 'constant'. We highlight some general features of the cosmological models that exist in these theories with reference to recent quasar data that are…

General Relativity and Quantum Cosmology · Physics 2012-12-11 John D. Barrow

Cosmography is a phenomenological and relatively model-independent approach to cosmology, where physical quantities are expanded as a Taylor series in the cosmological redshift, or in related variables. Here we apply this methodology to…

Cosmology and Nongalactic Astrophysics · Physics 2022-03-08 C. J. A. P. Martins , F. P. S. A. Ferreira , P. V. Marto

We review astrophysical, cosmological and terrestrial evidence for and against the constancy of fundamental parameters of particle physics, and discuss theoretical issues of unification and scalar-mediated forces, finding that the current…

High Energy Physics - Phenomenology · Physics 2008-11-26 Thomas Dent

We study the space-time evolution of the fine structure constant, $\alpha$, inside evolving spherical overdensities in a lambda-CDM Friedmann universe using the spherical infall model. We show that its value inside virialised regions will…

Astrophysics · Physics 2011-05-05 D. F. Mota , J. D. Barrow
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