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相关论文: Time Variation of the Fine Structure Constant Driv…

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We calculate bounds on the variation of the fine structure constant at the time of primordial nucleosynthesis and at the time of neutral hydrogen formation. We use these bounds and other bounds from the late universe to test Bekenstein…

天体物理学 · 物理学 2008-03-07 Mercedes E. Mosquera , Claudia G. Scoccola , Susana J. Landau , Hector Vucetich

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

In this note we observe that Webb and co-workers' observation of an evolving fine structure constant has since been reconfirmed. We also confirm Kuhne's contention that this implies a cosmological constant and exhibit a cosmological…

综合物理 · 物理学 2007-05-23 B. G. Sidharth

Changes in the values of the fundamental constants mu, the proton to electron mass ratio, and alpha, the fine structure constant due to rolling scalar fields have been discussed both in the context of cosmology and in new physics such as…

宇宙学与河外天体物理 · 物理学 2015-06-04 Rodger I. Thompson

Temporal and spatial variation of fine-structure constant $\alpha\equiv e^2/\hbar c$ in cosmology has been reported in analysis of combination Keck and VLT data. This paper studies this variation based on consideration of basic spacetime…

广义相对论与量子宇宙学 · 物理学 2015-09-02 Sze-Shiang Feng , Mu-Lin Yan

This paper presents the constraints on the time variation of the fine structure constant at recombination relative to its present value, Delta_alpha = (alpha_rec-alpha_0) / alpha_0, obtained from the analysis of the WMAP-3yr Cosmic…

天体物理学 · 物理学 2008-11-26 Petruta Stefanescu

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…

天体物理学 · 物理学 2011-05-05 D. F. Mota , J. D. Barrow

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…

原子物理 · 物理学 2015-06-26 Savely G. Karshenboim

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…

宇宙学与河外天体物理 · 物理学 2015-05-18 C. M. Gutierrez , M. Lopez-Corredoira

The Keck telescope's HIRES spectrograph has previously provided evidence for a smaller fine-structure constant, alpha, compared to the current laboratory value, in a sample of 143 quasar absorption systems: da/a=(-0.57+/-0.11)x10^{-5}. This…

宇宙学与河外天体物理 · 物理学 2009-11-25 Michael T. Murphy , John K. Webb , Victor V. Flambaum

We compare the sensitivity of a recent bound on time variation of the fine structure constant from optical clocks with bounds on time varying fundamental constants from atomic clocks sensitive to the electron-to-proton mass ratio, from…

宇宙学与河外天体物理 · 物理学 2010-05-26 Thomas Dent

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…

天体物理学 · 物理学 2009-11-10 H. Chand , R. Srianand , P. Petitjean , B. Aracil

We consider several transitions between narrow lines that have an enhanced sensitivity to a possible variation of the fine structure constant, alpha. This enhancement may allow a search to be performed with an effective suppression of the…

原子物理 · 物理学 2009-11-11 S. G. Karshenboim , A. Yu. Nevsky , E. J. Angstmann , V. A. Dzuba , V. V. Flambaum

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

We put bounds on the variation of the value of the fine structure constant $\alpha$, at the time of Big Bang nucleosynthesis. We study carefully all light elements up to $^7$Li. We correct a previous upper limit on $|\Delta \alpha /…

天体物理学 · 物理学 2009-10-31 L. Bergstrom , S. Iguri , H. Rubinstein

Sensitivity coefficients to temporal variation of the fine-structure constant alpha for transitions between the fine-structure (FS) sub-levels of the ground states of C I, Si I, S I, Ti I, Fe I, N II, Fe II, O III, S III, Ar III, Fe III, Mg…

天体物理学 · 物理学 2009-09-01 M. G. Kozlov , S. G. Porsev , S. A. Levshakov , D. Reimers , P. Molaro

We use the Cosmic Microwave Background (CMB) anisotropy data from Planck to constrain the spatial fluctuations of the fine-structure constant \alpha. Through Thompson scattering of CMB photons, spatial anisotropies of \alpha lead to…

宇宙学与河外天体物理 · 物理学 2013-06-07 Jon O'Bryan , Joseph Smidt , Francesco De Bernardis , Asantha Cooray

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…

宇宙学与河外天体物理 · 物理学 2017-05-10 S. A. Levshakov , M. G. Kozlov

We investigate the triple-alpha process and the Oklo phenomenon to obtain constraints on possible cosmological time variations of fundamental constants. Specifically we study cosmological temporal constraints for the fine structure constant…

天体物理学 · 物理学 2009-11-07 H. Oberhummer , A. Csoto , M. Fairbairn , H. Schlattl , M. M. Sharma