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相关论文: A Note on Transfinite M Theory and the Fine Struct…

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It is shown that the two sequences of characteristic dimensions of transfinite heterotic string space-time found by El Naschie can be remarkably well accounted for in terms of the arithmetic of self-conjugate homaloidal nets of plane…

综合物理 · 物理学 2008-11-26 Metod Saniga

We present the results of a new evaluation of the running fine structure constant $\alpha$ at the scale of the $Z$ mass in which the role of the $e^+e^-$ annihilation input data needed in this evaluation is minimized. This is achieved by…

高能物理 - 唯象学 · 物理学 2009-10-31 S. Groote , J. G. Körner , K. Schilcher , N. F. Nasrallah

We calculate the dependence of atomic transition frequencies on the fine structure constant, $\alpha = e^2/\hbar c$, for some ions of Ti, Mn, Na, C, and O. The results of these calculations will be used in the search for variation of alpha…

天体物理学 · 物理学 2007-05-23 J. C. Berengut , V. A. Dzuba , V. V. Flambaum , M. V. Marchenko

Corrections of orders $\alpha^5$ and $\alpha^6$ are calculated in the fine structure interval $\Delta E^{fs}=E(2P_{3/2})-E(2P_{1/2})$ and in the hyperfine structure of the energy levels $2P_{1/2}$ and $2P_{3/2}$ in muonic hydrogen. The…

高能物理 - 唯象学 · 物理学 2008-11-26 A. P. Martynenko

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 report a new measurement of the ratio $h/m_{\mathrm{Rb}}$ between the Planck constant and the mass of $^{87}\mathrm{Rb}$ atom. A new value of the fine structure constant is deduced, $\alpha^{-1}=137.035\,999\,037\,(91)$ with a relative…

(Abridged) Many-multiplet (MM) method applied to three inhomogeneous samples of Keck/HIRES quasar absorption spectra gives a shift in the value of the fine-structure constant of Delta alpha/alpha = (-5.4+/-1.2) 10^{-6} in the redshift range…

天体物理学 · 物理学 2017-08-23 Sergei A. Levshakov

We use the relativistic Hartree-Fock method, many-body perturbation theory and configuration-interaction method to calculate the dependence of atomic transition frequencies on the fine structure constant, alpha. The results of these…

原子物理 · 物理学 2008-11-26 J. C. Berengut , V. A. Dzuba , V. V. Flambaum , M. V. Marchenko

Measurements of the fine-structure constant alpha require methods from across subfields and are thus powerful tests of the consistency of theory and experiment in physics. Using the recoil frequency of cesium-133 atoms in a matter-wave…

原子物理 · 物理学 2018-12-14 Richard H. Parker , Chenghui Yu , Weicheng Zhong , Brian Estey , Holger Müller

Verification of theoretical predictions of an oscillating behavior of the fine-structure constant, alpha, with cosmic time requires high precision measurements at individual redshifts, while in earlier studies the mean Delta alpha/alpha…

天体物理学 · 物理学 2009-11-11 S. A. Levshakov , M. Centurion , P. Molaro , S. D'Odorico , D. Reimers , R. Quast , M. Pollmann

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…

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…

高能物理 - 唯象学 · 物理学 2025-06-24 K. A. Bronnikov , V. D. Ivashchuk , V. V. Khruschov

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

We analyze the decays $\phi \to K\bar{K}$ utilizing a formulation of transition rates which explicitly exhibits corrections to Fermi's Golden Rule. These corrections arise in systems in which the phase space and/or matrix element varies…

高能物理 - 唯象学 · 物理学 2008-11-26 E. Fischbach , A. W. Overhauser , B. Woodahl

In extensions of general relativity and in theories aiming at unifying gravity with the forces of the Standard Model, the value of the "fundamental constants" is often determined by the vacuum expectation value of new fields, which may thus…

广义相对论与量子宇宙学 · 物理学 2014-03-19 Cosimo Bambi

We report on an attempt to accurately wavelength calibrate four nights of data taken with the Keck HIRES spectrograph on QSO PHL957, for the purpose of determining whether the fine structure constant was different in the past. Using new…

宇宙学与河外天体物理 · 物理学 2009-12-15 Kim Griest , Jonathan B. Whitmore , Arthur M. Wolfe , J. Xavier Prochaska , J. Christopher Howk , Geoffrey W. Marcy

We analyze second-order $M1$-$M1$ and $M1$-$E2$ effects to the hyperfine structure (HFS) of the lowest energy $P$ states of alkali-metal atoms arising from the coupling of the two ($J=1/2,3/2$) fine-structure levels through the hyperfine…

原子物理 · 物理学 2011-07-13 K. Beloy , A. Derevianko

We reconsider the Re187 bound on the variation of the fine-structure constant. We combine the meteoritic measurement with several present-day lab measurements to firmly establish the quantitative upper limit to the time variation over the…

Radio-frequency E1 transitions between nearly degenerate, opposite parity levels of atomic dysprosium were monitored over an eight month period to search for a variation in the fine-structure constant. During this time period, data were…

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
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