English
Related papers

Related papers: Strong Limit on a Variable Proton-to-Electron Mass…

200 papers

We consider the influence of variation in the fine structure constant alpha on a promising experiment proposed by DeMille et al. to search for variation in the electron-to-proton mass ratio mu using diatomic molecules [DeMille et al., Phys.…

Atomic Physics · Physics 2011-11-15 K. Beloy , A. Borschevsky , V. V. Flambaum , P. Schwerdtfeger

We discuss how existing astrophysical measurements of various combinations of the fine-structure constant $\alpha$, the proton-to-electron mass ratio $\mu$ and the proton gyromagnetic ratio g$_{p}$ towards the radio source PKS1413+135 can…

Cosmology and Nongalactic Astrophysics · Physics 2013-10-01 A. M. R. V. L. Monteiro , M. C. Ferreira , M. D. Julião , C. J. A. P. Martins

In this paper, we show that methanol (CH3OH) torsional-rotational transitions, which have increased sensitivity to small variations of mu - the electron-to-proton mass ratio, are shifted relative to less sensitive transitions in the…

Astrophysics of Galaxies · Physics 2026-03-09 J. S. Vorotyntseva , S. A. Levshakov

A robust variational approach is used to investigate the sensitivity of the rotation-vibration spectrum of phosphine (PH$_3$) to a possible cosmological variation of the proton-to-electron mass ratio, $\mu$. Whilst the majority of computed…

Cosmology and Nongalactic Astrophysics · Physics 2018-08-17 Alec Owens , Sergei N. Yurchenko , Vladimir Špirko

We report deep Green Bank Telescope (GBT) spectroscopy in the redshifted NH$_3$~(1,1), CS~1-0 and H$_2$CO~0$_{\rm 00}$-1$_{\rm 01}$ lines from the $z \sim 0.685$ absorber towards B0218+357. The inversion (NH$_3$) and rotational (CS,…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 Nissim Kanekar

We report here the measurements of the energy spectra of atmospheric muons and of the cosmic ray primary proton and helium nuclei in a single experiment. These were carried out using the MASS superconducting spectrometer in a balloon flight…

High Energy Physics - Experiment · Physics 2008-11-26 MASS2 Collaboration

Astrophysical observations indicate a time variation of the proton-electron mass ratio and of the fine-structure constant. We discuss this phenomenon in models of Grand Unification. In these models a time variation of the fine-structure…

Astrophysics · Physics 2010-12-17 Xavier Calmet , Harald Fritzsch

The possibility of variations of the values of fundamental constants is a phenomenon predicted by a number of scenarios beyond General Relativity. This can happen if ``our'' fundamental constants are not the actual constants of the…

General Relativity and Quantum Cosmology · Physics 2024-07-12 Cosimo Bambi

Detection of high-redshift absorption in the optical spectra of quasars have provided a powerful tool to measure spatial and temporal variations of physical ``constants'' in the Universe. It is demonstrated that high sensitivity to the…

Atomic Physics · Physics 2009-10-31 V. A. Dzuba , V. V. Flambaum , J. K. Webb.

Numerical calculations of the sensitivity coefficients, Q_mu, of microwave molecular transitions in the ground torsion-rotation state of deuterated methanol (CH3OD, CD3OH, and CD3OD) to small variations in the fundamental physical constant…

High Energy Physics - Phenomenology · Physics 2024-06-18 J. S. Vorotyntseva , S. A. Levshakov , M. G. Kozlov

The muon anomalous magnetic moment is one of the most precisely measured quantities in particle physics. In a recent experiment at Brookhaven it has been measured with a remarkable 14-fold improvement of the previous CERN experiment…

High Energy Physics - Phenomenology · Physics 2015-05-13 Fred Jegerlehner , Andreas Nyffeler

We discuss the usage of measurements of the stability of nature's fundamental constants coming from comparisons between atomic clocks as a means to constrain coupled variations of these constants in a broad class of unification scenarios.…

High Energy Physics - Phenomenology · Physics 2012-12-19 M. C. Ferreira , M. D. Julião , C. J. A. P. Martins , A. M. R. V. L. Monteiro

Only astronomical observations can effectively probe in space-time the variabil ity of the physical dimensionless constants such as the fine structure constant and proton-to-electron mass ratio, \mu, which are related to fund amental forces…

Astrophysics · Physics 2007-12-31 Paolo Molaro

The persistent $a_\mu \equiv (g-2)/2$ anomaly in the muon sector could be due to new physics visible in the electron sector through a sub-ppb measurement of the anomalous magnetic moment of the electron $a_e$. Driven by recent results on…

High Energy Physics - Experiment · Physics 2014-05-27 F. Terranova , G. M. Tino

The muon anomalous magnetic moment is one of the most precisely measured quantities in particle physics. Recent high precision measurements (0.54ppm) at Brookhaven reveal a ``discrepancy'' by 3 standard deviations from the electroweak…

High Energy Physics - Phenomenology · Physics 2010-04-06 F. Jegerlehner

The electron and muon magnetic moments have played, and continue to play, important roles in testing the fundamental mathematical description of physical reality called the Standard Model of particle physics (SM). The electron magnetic…

High Energy Physics - Experiment · Physics 2026-02-17 Gerald Gabrielse , Graziano Venanzoni

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

We present high resolution optical spectra obtained with the Ultraviolet and Visual Echelle Spectrograph (UVES) at the Very Large Telescope (VLT) and 21-cm absorption spectra obtained with the Giant Metrewave Radio Telescope (GMRT) and the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-05 H. Rahmani , R. Srianand , N. Gupta , P. Petitjean , P. Noterdaeme , D. Albornoz Vasquez

The present constraints on fundamental constant variation (\alpha and \mu) obtained in the radio range are reviewed, coming essentially from absorption lines in front of quasars of intermediate to high-z galaxies, through CO, HI, OH, HCO+,…

Cosmology and Nongalactic Astrophysics · Physics 2009-10-06 F. Combes

We show how one can test the cosmological Poisson equation by requiring only the validity of three main assumptions: the energy-momentum conservation equations of matter, the equivalence principle, and the cosmological principle. We first…

Cosmology and Nongalactic Astrophysics · Physics 2024-05-08 Ziyang Zheng , Ziad Sakr , Luca Amendola
‹ Prev 1 3 4 5 6 7 10 Next ›