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相关论文: Testing cosmological variations of fundamental phy…

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One of the topical problems of contemporary physics is a possible variability of the fundamental constants. Here we consider possible variability of two dimensionless constants which are most important for calculation of atomic and…

原子物理 · 物理学 2016-09-08 D. A. Varshalovich , A. Y. Potekhin , A. V. Ivanchik

Endeavours of the unification of the four fundamental interactions have resulted in a development of theories having cosmological solutions in which low-energy limits of fundamental physical constants vary with time. The validity of such…

天体物理学 · 物理学 2011-05-23 A. V. Ivanchik , A. Y. Potekhin , D. A. Varshalovich

We report new upper limits on any possible long-term time variation of the ratio of the electron to proton masses, $(m_e/m_p)$, the fine-structure constant, ($\alpha$), and the quantity $\alpha^2 g_p(m_e/m_p)$, where $g_p$ is the proton…

天体物理学 · 物理学 2011-07-18 Lennox L. Cowie , Antoinette Songaila

Aims. To obtain limits on the variation of the fine-structure constant alpha and the electron-to-proton mass ratio mu over different cosmological epochs. Methods. A new approach based on the comparison of redshifts of far infrared (FIR)…

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

Most of the successful physical theories rely on the constancy of few fundamental quantities (such as the speed of light, $c$, the fine-structure constant, \alpha, the proton to electron mass ratio, \mu, etc), and constraining the possible…

天体物理学 · 物理学 2008-11-26 Raghunathan Srianand , Hum Chand , Patrick Petitjean , Bastien Aracil

We discuss experiments and observations aimed at testing the possible space-time variability of fundamental physical constants, predicted by the modern theory. Specifically, we consider two of the dimensionless physical parameters which are…

原子物理 · 物理学 2007-05-23 D. A. Varshalovich , A. Y. Potekhin , A. V. Ivanchik

We estimate the cosmological variation of the proton-to-electron mass ratio \mu=m_p/m_e by measuring the wavelengths of molecular hydrogen transitions in the early universe. The analysis is performed using high spectral resolution…

天体物理学 · 物理学 2009-11-07 A. Ivanchik , E. Rodriguez , P. Petitjean , D. Varshalovich

We summarize the attempts by our group and others to derive constraints on variations of fundamental constants over cosmic time using quasar absorption lines. Most upper limits reside in the range 0.5-1.5x10-5 at the 3sigma level over a…

宇宙学与河外天体物理 · 物理学 2015-05-13 Patrick Petitjean , Raghunathan Srianand , Hum Chand , Alexander Ivanchik , Pasquier Noterdaeme , Neeraj Gupta

The recent evidence for a cosmological evolution of the fine structure constant \alpha=e^2/\hbar c found from an analysis of absorption systems in the spectra of distant quasars, is modelled by a cosmological scenario in which it is assumed…

天体物理学 · 物理学 2007-05-23 J. W. Moffat

Spatial and temporal variations in the electron-to-proton mass ratio, mu, and in the fine-structure constant, alpha, are predicted in non-Standard models aimed to explain the nature of dark energy. Among them the so-called chameleon-like…

宇宙学与河外天体物理 · 物理学 2009-11-20 S. A. Levshakov , I. I. Agafonova , P. Molaro , D. Reimers

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…

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…

The fine-structure constant alpha does not vary as Friedmann Universes evolve, a conclusion based on assessments of quantum mechanics and electrodynamics. alpha = e^2/(4pi epsilon hbar c), where e is the charge of the electron, epsilon is…

天体物理学 · 物理学 2007-05-23 William Q. Sumner

Aims. We constrain a hypothetical variation in the fundamental physical constants over the course of cosmic time. Methods. We use unique observations of the CO(7-6) rotational line and the [CI] 3P_2 - 3P_1 fine-structure line towards a…

宇宙学与河外天体物理 · 物理学 2013-06-12 S. A. Levshakov , F. Combes , F. Boone , I. I. Agafonova , D. Reimers , M. G. Kozlov

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…

Astronomical observations have a unique ability to determine the laws of physics at distant times in the universe. They, therefore, have particular relevance in answering the basic question as to whether the laws of physics are invariant…

宇宙学与河外天体物理 · 物理学 2016-02-11 Rodger I. Thompson

Exotic cosmologies predict variability of the fundamental physical constants over the cosmic time. Using the VLT/UVES high resolution spectra of the quasar Q0347-3819 and unblended electronic - vibrational - rotational lines of the H2…

天体物理学 · 物理学 2014-10-13 S. A. Levshakov , M. Dessauges-Zavadsky , S. D'Odorico , P. Molaro

Observations of the redshift z=7.085 quasar J1120+0641 have been used to search for variations of the fine structure constant, alpha, over the redshift range 5.5 to 7.1. Observations at z=7.1 probe the physics of the universe when it was…

Within the context of mass-varying neutrinos, we construct a cosmological model that has a phase transition in the electromagnetic fine structure constant \alpha at a redshift of 0.5. The model accommodates hints of a time variable \alpha…

高能物理 - 唯象学 · 物理学 2008-11-26 L. Anchordoqui , V. Barger , H. Goldberg , D. Marfatia

Absorption spectroscopy toward high-redshift quasars provides strong constraints on the putative variation of fundamental constants of physics on cosmological time scales. The submillimeter ground-state transitions of methylidyne (CH) and…

宇宙学与河外天体物理 · 物理学 2026-02-25 S. Muller , A. Beelen , M. Guelin , J. H. Black , F. Combes , H. L. Bethlem , M. Gerin , C. Henkel , K. M. Menten , M. T. Murphy , W. Ubachs , N. Wozny
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