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A limit on a possible cosmological variation of the proton-to-electron mass ratio $\mu$ is derived from methanol (CH$_3$OH) absorption lines in the benchmark PKS1830$-$211 lensing galaxy at redshift $z = 0.89$ observed with the Effelsberg…

Cosmology and Nongalactic Astrophysics · Physics 2013-12-11 Julija Bagdonaite , Mario Daprà , Paul Jansen , Hendrick L. Bethlem , Wim Ubachs , Sébastien Muller , Christian Henkel , Karl M. Menten

This article summarizes the latest results on the proton-to-electron mass ratio $\mu$ derived from H$_2$ observations at high redshift in the light of possible variations of fundamental physical constants. The focus lies on UVES…

Cosmology and Nongalactic Astrophysics · Physics 2013-11-27 Martin Wendt , Paolo Molaro

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

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

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…

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

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…

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…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 Rodger I. Thompson

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…

The values of the fundamental constants such as $\mu = m_P/m_e$, the proton to electron mass ratio and $\alpha$, the fine structure constant, are sensitive to the product $\sqrt{\zeta_x^2(w+1)}$ where $\zeta_x$ is a coupling constant…

Cosmology and Nongalactic Astrophysics · Physics 2013-12-19 Rodger I. Thompson

This article summarizes the latest results on the proton-to-electron mass ratio $\mu$ derived from H$_2$ observations at high redshift in the light of possible variations of fundamental physical constants. The focus lies on UVES…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-17 Martin Wendt

The possibility of using astrophysical observations of rotational transitions in the methanol molecule to measure, or constrain temporal and spatial variations in the proton-to-electron mass ratio (mu) has recently been investigated by…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 Simon Ellingsen , Maxim Voronkov , Shari Breen

Spacetime variations of physical constants can be associated with the existence of Higgs-like scalar field(s) that couple non-universally to the baryonic matter. Recent results of astronomical spectral measurements of the fractional changes…

Cosmology and Nongalactic Astrophysics · Physics 2021-02-03 S. A. Levshakov

Far infrared fine-structure transitions of CI and CII and rotational transitions of CO are used to probe hypothetical variations of the electron-to-proton mass ratio mu = m_e/m_p at the epoch of reionization (z > 6). A constraint on Delta…

Cosmology and Nongalactic Astrophysics · Physics 2020-09-09 S. A. Levshakov , M. G. Kozlov , I. I. Agafonova

Many cosmological models invoke rolling scalar fields to account for the observed acceleration of the expansion of the universe. These theories generally include a potential V(phi) which is a function of the scalar field phi. Although…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-11 Rodger I. Thompson , C. J. A. P. Martins , P. E. Vielzeuf

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

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

A high signal-to-noise spectrum covering the largest number of hydrogen lines (90 H2 lines and 6 HD lines) in a high redshift object was analyzed from an observation along the sight-line to the bright quasar source J2123$-$005 with the UVES…

Cosmology and Nongalactic Astrophysics · Physics 2011-05-23 Freek van Weerdenburg , Michael T. Murphy , Adrian L. Malec , Lex Kaper , Wim 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 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
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