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The possible cosmological variation of the proton-to-electron mass ratio was estimated by measuring the H_2 wavelengths in the high-resolution spectrum of the quasar Q~0347-382. Our analysis yielded an estimate for the possible deviation of…

Astrophysics · Physics 2009-11-07 A. Ivanchik , P. Petitjean , E. Rodriguez , D. Varshalovich

We present a strong constraint on variation of the proton-to-electron mass ratio, mu, over cosmological time scales using molecular hydrogen transitions in optical quasar spectra. Using high quality spectra of quasars Q0405-443, Q0347-383…

Astrophysics · Physics 2010-05-12 Julian A. King , John K. Webb , Michael T. Murphy , Robert F. Carswell

Exploring physics beyond General Relativity and the Standard Model of Particle Physics involves investigating spacetime variations in natural constants. This study employs an $H_2$-single of QSO 0347-383 observational spectrum to propose a…

Cosmology and Nongalactic Astrophysics · Physics 2024-09-09 T. D. Le

Multidimensional cosmologies allow for variations of fundamental physical constants over the course of cosmological evolution, and different versions of the theories predict different time dependences. In particular, such variations could…

The Standard Model of particle physics assumes that the so-called fundamental constants are universal and unchanging. Absorption lines arising in molecular clouds along quasar sightlines offer a precise test for variations in the…

Astrophysics · Physics 2009-08-18 Michael T. Murphy , Victor V. Flambaum , Sebastien Muller , Christian Henkel

A new limit on the possible cosmological variation of the proton-to-electron mass ratio \mu=m_p/m_e is estimated by measuring wavelengths of H_2 lines of Lyman and Werner bands from two absorption systems at z_abs = 2.5947 and 3.0249 in the…

Astrophysics · Physics 2009-11-13 A. Ivanchik , P. Petitjean , D. Varshalovich , B. Aracil , R. Srianand , H. Chand , C. Ledoux , P. Boisse

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…

Astrophysics · Physics 2014-10-13 S. A. Levshakov , M. Dessauges-Zavadsky , S. D'Odorico , P. Molaro

So far the only seemingly significant indication of a cosmological variation exists for the proton-to-electron mass ratio as stated by Reinhold et al. (2006). The measured indication of variation is based on the combined analysis of H2…

Astrophysics · Physics 2009-06-23 Martin Wendt , Dieter Reimers

Motivated by recent astrophysical observations of quasar absorption systems, we formulate a simple theory where the electron to proton mass ratio $\mu =m_{e}/m_{p}$ is allowed to vary in space-time. In such a minimal theory only the…

Astrophysics · Physics 2009-11-10 John D Barrow , Joao Magueijo

Molecular hydrogen transitions in the sub-damped Lyman alpha absorber at redshift z = 2.69, toward the background quasar SDSS J123714.60+064759.5, were analyzed in order to search for a possible variation of the proton-to-electron mass…

Cosmology and Nongalactic Astrophysics · Physics 2015-09-30 M. Daprà , J. Bagdonaite , M. T. Murphy , W. Ubachs

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…

Astrophysics · Physics 2007-05-23 D. A. Varshalovich , A. Y. Potekhin , A. V. Ivanchik , V. E. Panchuk , K. M. Lanzetta

In an effort to resolve the discrepancy between two measurements of the fundamental constant mu, the proton to electron mass ratio, at early times in the universe we reanalyze the same data used in the earlier studies. Our analysis of the…

Molecular hydrogen absorption in the damped Lyman-alpha system at z = 2.34 towards quasar Q1232+082 is analyzed in order to derive a constraint on a possible temporal variation of the proton-to-electron mass ratio, mu, over cosmological…

Cosmology and Nongalactic Astrophysics · Physics 2017-01-11 M. Daprà , M. van der Laan , M. T. Murphy , W. Ubachs

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…

Cosmology and Nongalactic Astrophysics · Physics 2009-11-20 S. A. Levshakov , I. I. Agafonova , P. Molaro , D. Reimers

The variation of the dimensionless fundamental physical constant mu = m_p/m_e (the proton to electron mass ratio) can be constrained via observation of Lyman and Werner lines of molecular hydrogen in the spectra of damped Lyman alpha…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 Martin Wendt , Paolo Molaro

The variation of the dimensionless fundamental physical constant mu=m_p/m_e can be checked through observation of Lyman and Werner lines of molecular hydrogen in the spectra of distant QSOs. Our intention is to asses the accuracy of the…

Cosmology and Nongalactic Astrophysics · Physics 2016-02-03 Martin Wendt , Paolo Molaro

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…

Atomic Physics · Physics 2016-09-08 D. A. Varshalovich , A. Y. Potekhin , A. V. Ivanchik

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…

Astrophysics · Physics 2011-07-18 Lennox L. Cowie , Antoinette Songaila

Molecular transitions recently discovered at redshift z_abs=2.059 toward the bright background quasar J2123-0050 are analysed to limit cosmological variation in the proton-to-electron mass ratio, mu=m_p/m_e. Observed with the Keck…

That the laws of physics are the same at all times and places throughout the Universe is one of the basic assumptions of physics. Astronomical observations provide the only means to test this basic assumption on cosmological time and…

Instrumentation and Methods for Astrophysics · Physics 2019-04-10 Xi Chen , Simon P. Ellingsen , Ying Mei
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