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相关论文: Space-time variation of the fine structure constan…

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A method offering an order of magnitude sensitivity gain is described for using quasar spectra to investigate possible time or space variation in the fine structure constant, alpha. Applying the technique to a sample of 30 absorption…

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…

天体物理学 · 物理学 2009-08-18 V. A. Dzuba , V. V. Flambaum , M. T. Murphy , J. K. Webb

Dependence of transition frequencies on the fine structure constant $\alpha=e^2/\hbar c$ is calculated for several many-electron systems which are used or planned to be used in the laboratory search for the time variation of the fine…

原子物理 · 物理学 2009-11-13 V. A. Dzuba , V. V. Flambaum

Theories unifying gravity with other interactions suggest spatial and temporal variation of fundamental "constants" in the Universe. A change in the fine structure constant, alpha, could be detected via shifts in the frequencies of atomic…

宇宙学与河外天体物理 · 物理学 2015-05-20 J. C. Berengut , V. A. Dzuba , V. V. Flambaum , J. A. King , M. G. Kozlov , M. T. Murphy , J. K. Webb

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…

天体物理学 · 物理学 2009-10-31 Manoj Kaplinghat , Robert J. Scherrer , Michael S. Turner

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…

A possibility for fundamental constants to vary in time is suggested by theories unifying gravity with other interactions. In this article we examine proposals to use optical transitions of Sr, Dy, YbII and YbIII for the search of the time…

原子物理 · 物理学 2009-02-05 V. A. Dzuba , V. V. Flambaum , M. V. Marchenko.

Contemporary multidimensional cosmological theories predict different variations of fundamental physical constants in course of the cosmological evolution. On the basis of the QSO spectra analysis, we show that the fine-structure constant…

天体物理学 · 物理学 2007-05-23 D. A. Varshalovich , A. Y. Potekhin , A. V. Ivanchik , V. E. Panchuk , K. M. Lanzetta

There are indications from the study of quasar absorption spectra that the fine structure constant $\alpha$ may have been measurably smaller for redshifts $z>2.$ Analyses of other data ($^{149}$Sm fission rate for the Oklo natural reactor,…

高能物理 - 唯象学 · 物理学 2009-11-10 Luis Anchordoqui , Haim Goldberg

Theories unifying gravity with other interactions suggest spatial and temporal variation of fundamental ``constants'' in the Universe. A change in the fine structure constant, alpha, could be detected via shifts in the frequencies of atomic…

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…

原子物理 · 物理学 2022-06-22 V. A. Dzuba , V. V. Flambaum , M. T. Murphy , D. A. Berke

We review some of the history and properties of theories for the variation of the gravitation and fine structure 'constants'. We highlight some general features of the cosmological models that exist in these theories with reference to…

广义相对论与量子宇宙学 · 物理学 2014-11-17 John D. Barrow

The remarkable detection of a spatial variation in the fine-structure constant, alpha, from quasar absorption systems must be independently confirmed by complementary searches. In this letter, we discuss how terrestrial measurements of…

原子物理 · 物理学 2012-09-11 J. C. Berengut , V. V. Flambaum

Evidence that the fine structure constant, alpha, was different in an early epoch has recently been found in quasar (QSO) absorption spectra. An accurate laboratory measurement of alpha variation could help to distinguish between space and…

原子物理 · 物理学 2016-09-08 E. J. Angstmann , V. A. Dzuba , V. V. Flambaum

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…

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

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

The search for variation of the fundamental constants such as the fine structure constant $\alpha$ ($\alpha=e^2/\hbar c$) and the ratios of fundamental masses (e.g., electron to proton mass ratio $\mu=m_e/m_p$) is reviewed. Strong emphasis…

原子物理 · 物理学 2015-05-13 V. V. Flambaum , V. A. Dzuba

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 calculated the dependence of the transition frequencies on the fine-structure constant $\alpha$ ($q$-factors) for Ni~II. Nickel is one of the few elements with high sensitivity to $\alpha$-variation, whose lines are observed at high…

原子物理 · 物理学 2014-11-03 E. A. Konovalova , M. G. Kozlov , R. T. Imanbaeva
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