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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…

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

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

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

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…

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

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

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

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 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

An overview is presented of the H$_2$ quasar absorption method to search for a possible variation of the proton--electron mass ratio $\mu=m_p/m_e$ on a cosmological time scale. Details of the analysis of astronomical spectra, obtained with…

Astrophysics of Galaxies · Physics 2016-05-25 Wim Ubachs , Julija Bagdonaite , Edcel J. Salumbides , Michael T. Murphy , Lex Kaper

We study variation of the proton-to-electron mass ratio $ \mu=m_{p}/m_{e} $ by incorporating standard model (SM) of particle physics into an extended Brans-Dicke theory. We show that the evolution of the Higgs vacuum expectation value…

General Relativity and Quantum Cosmology · Physics 2019-11-13 Ahmad Mohamadnejad

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…

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

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

A molecular hydrogen absorber at a lookback time of 12.4 billion years, corresponding to 10$\%$ of the age of the universe today, is analyzed to put a constraint on a varying proton--electron mass ratio, $\mu$. A high resolution spectrum of…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-23 J. Bagdonaite , W. Ubachs , M. T. Murphy , J. B. Whitmore

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

We determine the sensitivity to a possible variation of the proton-to-electron mass ratio \mu for torsion-wagging-rotation transitions in the ground state of methylamine (CH3NH2). Our calculation uses an effective Hamiltonian based on a…

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 transitions in quasar spectra can be used to constrain variation in the proton-to-electron mass ratio, $\mu\equiv m_p/m_e$, at high redshifts ($z\gtrsim 2$). We present here an analysis of a new spectrum of the quasar…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-28 Julian A. King , Michael T. Murphy , Wim Ubachs , John K. Webb
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