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Related papers: Varying Alpha

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Rolling tachyon field models are among the candidates suggested as explanations for the recent acceleration of the Universe. In these models the field is expected to interact with gauge fields and lead to variations of the fine-structure…

Cosmology and Nongalactic Astrophysics · Physics 2016-06-28 C. J. A. P. Martins , F. M. O. Moucherek

Any time variation in the fine-structure constant alters the ionization history of the universe and therefore changes the pattern of cosmic microwave background fluctuations. We calculate the changes in the spectrum of these fluctuations as…

Astrophysics · Physics 2009-10-31 Manoj Kaplinghat , Robert J. Scherrer , Michael S. Turner

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

Bekenstein's model of a scalar field, \phi, that affects the electromagnetic permeability (usually identified with ``changing \alpha'') predicts tiny variations of the effective fine structure constant up to very high red-shifts,…

High Energy Physics - Phenomenology · Physics 2009-09-15 Keith A. Olive , Maxim Pospelov

By employing Dirac LNH, and a further generalization by Berman (GLNH), we estimate how should vary the total number of nucleons, the energy density, Newton Gravitational constant, the cosmological constant, the magnetic permeability and…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Marcelo S. Berman , Luis A. Trevisan

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

Starting from astrophysical indications that the fine structure constant might undergo a small cosmological time shift, we discuss the implications of such an effect from the point of view of particle physics. Grand unification implies…

High Energy Physics - Phenomenology · Physics 2011-09-13 Xavier Calmet , Harald Fritzsch

We search for the most suitable set of cosmological parameters that describes the observable universe. The search includes the possibility of quintessential flat universes, i.e., the analysis is restricted to the determination of the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 Ariel Zandivarez , Hector J. Martinez

In this work, we consider the so-called $\Lambda(\alpha)$CDM cosmology with $\Lambda\propto\alpha^{-6}$ while the fine-structure "constant" $\alpha$ is varying. In this scenario, the accelerated expansion of the universe is driven by the…

General Relativity and Quantum Cosmology · Physics 2017-11-16 Hao Wei , Dong-Ze Xue

We consider the problem of the evolution of the fine structure coefficient alpha under the assumption that the scalar field coupling to the Maxwell term satisfies the condition mt>>1 for coherent dark matter oscillations. In this case we…

Astrophysics · Physics 2009-11-10 M. G. Barnett , R. Dick , K. E. Wunderle

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

Theories unifying gravity and other interactions suggest the possibility of spatial and temporal variation of physical ``constants'' in the Universe. Detection of high redshift absorption systems intersecting the sight lines towards distant…

Astrophysics · Physics 2009-08-18 V. A. Dzuba , V. V. Flambaum , M. T. Murphy , J. K. Webb

Sensitivity of the frequencies of twenty two atomic transitions to the variation of the fine structure constant $\alpha$ is calculated. The findings are to be used in search for possible variation of $\alpha$ across our Galaxy using high…

Atomic Physics · Physics 2022-06-22 V. A. Dzuba , V. V. Flambaum , M. T. Murphy , D. A. Berke

Attempts to measure the variability of the fine structure constant alpha over cosmological time, using spectra of high redshift quasars have produced conflicting results. We use the Many Multiplet (MM) method with Mg II and Fe II lines on…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-22 A. Songaila , L. L. Cowie

We examine the evolution of a closed, homogeneous and anisotropic cosmology subject to a variation of the fine structure 'constant', \alpha, within the context of the theory introduced by Bekenstein, Sandvik, Barrow and Magueijo, which…

General Relativity and Quantum Cosmology · Physics 2015-06-15 John D. Barrow , David Sloan

I motivate and discuss some recent work on theories with varying constants, and consider some possible observational consequences and tests. Particular emphasis is given to models which can (almost) exactly mimic the predictions of standard…

Astrophysics · Physics 2017-08-23 C. J. A. P. Martins

We formulate a simple extension of general relativity which incorporates space-time variations in the Newtonian gravitation 'constant', $G$, and the fine structure 'constant', $\alpha $, which generalises Brans-Dicke theory and our theory…

Astrophysics · Physics 2014-10-13 J. D. Barrow , J. Magueijo , H. B. Sandvik

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 analyze different data of the variation of the fine structure constant obtained with different methods to check their consistency.We test consistency using the modified Student test and confidence intervals. We split the data sets in…

Astrophysics · Physics 2009-11-13 Susana J. Landau , Claudio Simeone

Star-forming galaxies at high redshifts are the ideal targets to probe the hypothetical variation of the fine-structure constant alpha over cosmological time scales. We propose a modification of the alkali doublets method which allows us to…

Cosmology and Nongalactic Astrophysics · Physics 2017-05-10 S. A. Levshakov , M. G. Kozlov
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