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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

We study the cosmological constraints of the time variation of the electron mass $m_e$ and the fine-structure constant $\alpha$, using data of cosmic microwave background, supernovae light curve and baryon acoustic oscillation (BAO) data…

Cosmology and Nongalactic Astrophysics · Physics 2025-04-15 Yo Toda , Osamu Seto

We study the cosmological evolution of the fine structure constant, $\alpha$, and the proton-to-electron mass ratio, $\mu=m_p/m_e$, in the context of a generic class of models where the gauge kinetic function is a linear function of a…

Astrophysics · Physics 2008-11-26 P. P. Avelino

The optical spectra of objects classified as QSOs in the SDSS DR6 are analyzed with the aim of determining the value of the fine structure constant in the past and then check for possible changes in the constant over cosmological…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 C. M. Gutierrez , M. Lopez-Corredoira

This letter explores how a reinterpretation of the generalized uncertainty principle as an effective variation of Planck's constant provides a physical explanation for a number of fundamental quantities and couplings. In this context, a…

General Physics · Physics 2024-09-02 Ahmed Farag Ali , Jonas Mureika , Elias C. Vagenas , Ibrahim Elmashad

Tests of the stability of nature's fundamental constants are one of the cornerstones of the ongoing search for the new physics which is required to explain the recent acceleration of the universe. The two main settings for these tests are…

Cosmology and Nongalactic Astrophysics · Physics 2019-04-18 C. J. A. P. Martins , M. Vila Miñana

A brief description of the main methods for determining the fine structure constant is given. It is shown that the exact value of the fine structure constant is important for the new International System of Units (SI) and for fundamental…

High Energy Physics - Phenomenology · Physics 2025-06-24 K. A. Bronnikov , V. D. Ivashchuk , V. V. Khruschov

We consider the effect of the coupled variations of fundamental constants on the nucleon magnetic moment. The nucleon g-factor enters into the interpretation of the measurements of variations in the fine-structure constant, alpha, in both…

High Energy Physics - Phenomenology · Physics 2011-12-19 Feng Luo , Keith A. Olive , Jean-Philippe Uzan

Gravitational anomalies such as the mine/borehole g anomaly, the near-flatness of the spiral galaxy rotation-velocity curves, currently interpreted as a `dark matter' effect, the absence of that effect in ordinary elliptical galaxies, and…

General Physics · Physics 2007-05-23 Reginald T. Cahill

Higher-dimensional theories have the remarkable feature of predicting a time (and hence redshift) dependence of the `fundamental' four dimensional constants on cosmological timescales. In this paper we update the bounds on a possible…

We propose a phenomenological approach to the cosmological constant problem based on generally covariant non-local and acausal modifications of four-dimensional gravity at enormous distances. The effective Newton constant becomes very small…

High Energy Physics - Theory · Physics 2007-05-23 Nima Arkani-Hamed , Savas Dimopoulos , Gia Dvali , Gregory Gabadadze

By measuring the fundamental constants in astrophysical objects one can test basic physical principles as space-time invariance of physical laws along with probing the applicability limits of the standard model of particle physics. The…

Instrumentation and Methods for Astrophysics · Physics 2016-03-07 S. A. Levshakov

We describe a rigorous construction, using matched asymptotic expansions, which establishes under very general conditions that local terrestrial and solar-system experiments will measure the effects of varying `constants' of Nature…

General Relativity and Quantum Cosmology · Physics 2011-07-19 Douglas J. Shaw , John D. Barrow

Detecting any evolution of dimensionless in the ratios of physical quantities, such as the fine structure constant, would prove that the Weak Equivalence Principle is violated and lead to a paradigm shift in physics. High resolution…

Cosmology and Nongalactic Astrophysics · Physics 2023-10-03 Dinko Milaković

In this thesis, we focus on the study of the variation of the electron mass $m_e$, and the fine structure constant $\alpha$, at different cosmic times. We analyze the details of the recombination physics, including helium recombination, in…

Cosmology and Nongalactic Astrophysics · Physics 2009-06-02 Claudia G. Scóccola

In the metric approach of $f(R)$ theories of gravity, the fourth-order field equations are often recast as effective Einstein equations in the presence of standard matter and a curvature fluid (which gathers all the extra terms), always in…

General Relativity and Quantum Cosmology · Physics 2020-12-01 Juan M. Z. Pretel , Sergio E. Jorás , Ribamar R. R. Reis

We make use of Dirac LNH and results for a time varying fine structure constant in order to derive possible laws of variation for speed of light, the number of nucleons in the Universe, energy density and gravitational constant. By…

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

This paper introduces new tests of fundamental physics by means of the analysis of disturbances on the GNSS signal propagation. We show how the GNSS signals are sensitive to a space variation of the fine structure constant $\alpha$ in a…

High Energy Physics - Phenomenology · Physics 2020-12-09 Bruno Bertrand , Pascale Defraigne

The fine structure constant $\alpha $ includes the speed of light as given by $\alpha =\frac{e^{2}}{4\pi \epsilon_{0}c\hbar}$. It is shown here that, following a $TH\epsilon \mu $ formalism, interpreting the permittivity $\epsilon_{0}$ and…

General Relativity and Quantum Cosmology · Physics 2009-08-25 Antonio Alfonso-Faus

We perform accurate calculations of the dependence of transition frequencies in two valence electron atoms and ions on a variation of the fine structure constant, alpha. The relativistic Hartree-Fock method is used with many-body…

Atomic Physics · Physics 2009-02-05 E. J. Angstmann , V. A. Dzuba , V. V. Flambaum
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