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相关论文: Cosmological Variation of the Fine Structure Const…

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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…

天体物理学 · 物理学 2007-05-23 Jacob D. Bekenstein

We show that using the modified form of the Dirac Hamiltonian as suggested by Bekenstein, does not affect the analysis in [1-4] of QSO data pertaining to a measurement of alpha variation. We obtain the present time limit on Bekenstein's…

天体物理学 · 物理学 2009-08-18 E. J. Angstmann , V. V. Flambaum , S. G. Karshenboim

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…

天体物理学 · 物理学 2009-10-31 John D. Barrow , Joao Magueijo

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…

广义相对论与量子宇宙学 · 物理学 2007-05-23 Marcelo S. Berman , Luis A. Trevisan

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,…

高能物理 - 唯象学 · 物理学 2009-09-15 Keith A. Olive , Maxim Pospelov

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 $\alpha$…

广义相对论与量子宇宙学 · 物理学 2012-05-11 K. A. Bronnikov , S. A. Kononogov

Motivated by reported claims of the measurements of a variation of the fine structure constant $\alpha$ we consider a theory where the electric charge, and consequently $\alpha$, is not a constant but depends on the Ricci scalar $R$. %We…

宇宙学与河外天体物理 · 物理学 2014-03-11 Antonio Enea Romano

I review recent constraints on and claimed detections of a time-varying fine-structure constant $\alpha$, and discuss our own work, particularly on the effects of $\alpha$ in the cosmic microwave background and large-scale structure. Our…

天体物理学 · 物理学 2007-05-23 C. J. A. P. Martins

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…

天体物理学 · 物理学 2007-05-23 R. W. Kuhne

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…

广义相对论与量子宇宙学 · 物理学 2015-01-20 Alexander A. H. Graham

Inspired by recent claims for a varying fine structure constant, alpha, we investigate the effect of ``promoting coupling constants to variables'' upon various parameters of the standard model. We first consider a toy model: Proca's theory…

高能物理 - 唯象学 · 物理学 2009-11-10 Dagny Kimberly , Joao Magueijo

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…

广义相对论与量子宇宙学 · 物理学 2007-05-23 Marcelo S. Berman , Luis A. Trevisan

In present paper we evaluate the fine structure constant variation, that should take place as the Universe expands and its curvature is changed adiabatically. Such variation of the fine structure constant is attributed to an energy losses…

综合物理 · 物理学 2020-12-15 Anton A. Lipovka , Ivan A. Cardenas

We propose to generalize Bekenstein model for the time variation of the fine structure "constant" $\alpha_{em}$ to QCD strong coupling constant $\alpha_S$. We find that, except for a ``fine tuned'' choice of the free parameters, the…

天体物理学 · 物理学 2011-07-19 N. Chamoun , S. J. Landau , H. Vucetich

Recent work by Webb {\it et al.} has provided indications of spatial variations of the fine-structure constant, $\alpha$, at a level of a few parts per million. Using a dataset of 293 archival measurements, they further show that a dipole…

宇宙学与河外天体物理 · 物理学 2016-03-16 A. M. M. Pinho , C. J. A. P. Martins

The fine structure constant, alpha, is shown to be proportional to the ratio of the quanta of electric and magnetic flux of force of the electron, and provides a new representation, which is global across all unit systems. Consequently, a…

高能物理 - 唯象学 · 物理学 2023-03-14 Michael Edmund Tobar

In the present work, we consider the cosmological constant model $\Lambda\propto\alpha^{-6}$, which is well motivated from three independent approaches. As is well known, the hint of varying fine structure constant $\alpha$ was found in…

广义相对论与量子宇宙学 · 物理学 2017-01-10 Hao Wei , Xiao-Bo Zou , Hong-Yu Li , Dong-Ze Xue

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…

天体物理学 · 物理学 2008-11-26 Kazuhide Ichikawa , Toru Kanzaki , Masahiro Kawasaki

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:…

高能物理 - 唯象学 · 物理学 2009-11-10 Charles L. Steinhardt

We describe the results of a search for time variability of the fine structure constant, alpha, using absorption systems in the spectra of distant quasars. Three large optical datasets and two 21cm/mm absorption systems provide four…

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