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Related papers: Varying Constants

200 papers

A new method based on large-scale structure observations is proposed to probe a possible time variation of the fine-structure constant ($\alpha$). Our analyses are based on time-delay of Strong Gravitational Lensing and Type Ia Supernovae…

Cosmology and Nongalactic Astrophysics · Physics 2021-09-09 L. R. Colaço , J. E. Gonzalez , R. F. L. Holanda

The time variation of fundamental mass scales can have profound cosmological implications. We investigate a particular model of crossover quintessence which is compatible with all present cosmological observations. This model can also…

High Energy Physics - Phenomenology · Physics 2017-08-23 C. Wetterich

We search for transient variations of the fine structure constant using data from a European network of fiber-linked optical atomic clocks. By searching for coherent variations in the recorded clock frequency comparisons across the network,…

Development of fundamental physics relies on the constancy of various fundamental quantities such as the fine structure constant. Detecting or constraining the possible time variations of these fundamental physical quantities is an…

Astrophysics · Physics 2009-11-10 H. Chand , R. Srianand , P. Petitjean , B. Aracil

Inaba recently used a simple model to suggest that Quantum Theory can result from a fluctuation in the cosmos. In this note we confirm this conclusion from a different and more general point of view. We then argue that this provides an…

General Physics · Physics 2007-05-23 B. G. Sidharth

Detection of high-redshift absorption in the optical spectra of quasars have provided a powerful tool to measure spatial and temporal variations of physical ``constants'' in the Universe. It is demonstrated that high sensitivity to the…

Atomic Physics · Physics 2009-10-31 V. A. Dzuba , V. V. Flambaum , J. K. Webb.

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

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

In this paper we compare the dimensional method with the Lie groups tactic in order to show the limitations and advantages of each technique. For this purpose we study in detail a perfect fluid cosmological model with time-varying…

General Relativity and Quantum Cosmology · Physics 2009-09-29 José Antonio Belinchón

Discussion of the constancy, or otherwise, of the various so-called universal constants which abound in physics has continued for many years. However, relatively recent observations, which appear to indicate a variation in the value of the…

General Physics · Physics 2007-08-21 A. D. Law , J. Dunning-Davies

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

We review some string-inspired theoretical models which incorporate a correlated spacetime variation of coupling constants while remaining naturally compatible both with phenomenological constraints coming from geochemical data (Oklo;…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Thibault Damour

We review the observational information on the constancy of the fine structure constant alpha. We find that small improvements on the measurement of ^{187}Re lifetime can provide significant progress in exploring the range of variability…

Astrophysics · Physics 2009-11-07 G. Fiorentini , B. Ricci

We consider the evolution of a flat Friedmann-Roberstson-Walker Universe in a higher derivative theories, including $\alpha R^{2}$ terms to the Einstein-Hilbert action in the presence of a variable gravitational and cosmological constants.…

General Relativity and Quantum Cosmology · Physics 2014-11-17 P. S. Debnath , B. C. Paul

Crossover quintessence predicts that the time variation of fundamental couplings is substantially faster at redshift $z\approx 2$ than over the past few billion years. This could reconcile the reported time variation of the fine structure…

High Energy Physics - Phenomenology · Physics 2014-11-17 C. Wetterich

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

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

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

We study the observed small deviations of high-redshift absorption spectra that are interpreted as a possible evidence for a variable fine structure constant. On the contrary, we claim that the effect could be completely attributed to the…

Astrophysics · Physics 2010-11-11 D. Palle

It is possible that fundamental constants may not be constant at all. There is a generally accepted view that one can only talk about variations of dimensionless quantities, such as the fine structure constant $\alpha_{\rm e}\equiv…

Cosmology and Nongalactic Astrophysics · Physics 2011-01-27 Adam Moss , Ali Narimani , Douglas Scott