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We investigate a link between the running of the fine structure constant $\alpha$ and a time evolving scalar dark energy field. Employing a versatile parameterization for the equation of state, we exhaustively cover the space of dark energy…

Astrophysics · Physics 2009-11-10 Michael Doran

Recent updated results of quasar spectra suggested a 3.9$\sigma$ significance of spatial variation of the fine-structure constant. Theoretically, it is important to examine whether the fine-structure constant, as a fundamental constant in…

General Relativity and Quantum Cosmology · Physics 2020-11-17 Zhe Chang , Qing-Hua Zhu

We investigate the variation of the fine-structure constant, {\alpha}, in symmetron models using N-body simulations in which the full spatial distribution of {\alpha} at different redshifts has been calculated. In particular, we obtain…

Cosmology and Nongalactic Astrophysics · Physics 2014-01-29 Marvin F. Silva , Hans A. Winther , David F. Mota , C. J. A. P. Martins

We perform calculations of the dependence of nuclear magnetic moments on quark masses and obtain limits on the variation of the ratio of quark mass and strong interaction scale (m_q/Lambda_{QCD}) from recent atomic clock experiments with…

Atomic Physics · Physics 2016-09-08 V. V. Flambaum

Radio-frequency electric-dipole transitions between nearly degenerate, opposite parity levels of atomic dysprosium (Dy) were monitored over an eight-month period to search for a variation in the fine-structure constant, $\alpha$. The data…

We calculate sensitivity coefficients to $\alpha$-variation for the fine-structure transitions (1,0) and (2,1) within $^3P_J[2s^2 2p^2]$ multiplet of the Carbon-like ions C I, N II, O III, Na VI, Mg VII, and Si IX. These transitions lie in…

Atomic Physics · Physics 2009-03-10 M. G. Kozlov , I. I. Tupitsyn , D. Reimers

Sensitivity of atomic transition frequencies to variation of the fine structure constant $\alpha=e^2/\hbar c$ increases proportional to $Z^2$ where $Z$ is the nuclear charge. Recently several lines of heavy ions Ge II, Sn II and Pb II have…

Astrophysics · Physics 2009-08-18 V. A. Dzuba , V. V. Flambaum

We demonstrate that recent measurements of Cosmic Microwave Background temperature and polarization anisotropy made by the ACBAR, QUAD and BICEP experiments substantially improve the cosmological constraints on possible variations of the…

Cosmology and Nongalactic Astrophysics · Physics 2010-10-28 Eloisa Menegoni , Silvia Galli , James Bartlett , Carlos J. A. P. Martins , Alessandro Melchiorri

The formation of the cosmic microwave background radiation (CMBR) provides a very powerful probe of the early universe at the epoch of recombination. Specifically, it is possible to constrain the variation of fundamental physical constants…

Astrophysics · Physics 2009-10-31 Steen Hannestad

We report on an attempt to accurately wavelength calibrate four nights of data taken with the Keck HIRES spectrograph on QSO PHL957, for the purpose of determining whether the fine structure constant was different in the past. Using new…

Cosmology and Nongalactic Astrophysics · Physics 2009-12-15 Kim Griest , Jonathan B. Whitmore , Arthur M. Wolfe , J. Xavier Prochaska , J. Christopher Howk , Geoffrey W. Marcy

In extensions of general relativity and in theories aiming at unifying gravity with the forces of the Standard Model, the value of the "fundamental constants" is often determined by the vacuum expectation value of new fields, which may thus…

General Relativity and Quantum Cosmology · Physics 2014-03-19 Cosimo Bambi

The fine structure constant, alpha, is shown to be proportional to the ratio of the quanta of electric and magnetic flux of force of the electron, and provides a new representation, which is global across all unit systems. Consequently, a…

High Energy Physics - Phenomenology · Physics 2023-03-14 Michael Edmund Tobar

We study atomic systems that are in the frequency range of optical atomic clocks and have enhanced sensitivity to potential time-variation of the fine structure constant, alpha. The high sensitivity is due to coherent contributions from…

Atomic Physics · Physics 2010-09-16 J. C. Berengut , V. A. Dzuba , V. V. Flambaum

Optical quasar spectra can be used to trace variations of the fine-structure constant alpha. Controversial results that have been published in last years suggest that in addition to to wavelength calibration problems systematic errors might…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-16 Nils Prause , Dieter Reimers

We search for a variation of the electromagnetic fine structure constant ($\alpha \equiv e^2/\hbar c$) using a sample of 58 SZ selected clusters in the redshift range ($0.2<z<1.5$) detected by the South Pole Telescope, along with X-ray…

Cosmology and Nongalactic Astrophysics · Physics 2021-02-12 Kamal Bora , Shantanu Desai

The fine-structure constant, $\alpha$, controls the strength of the electromagnetic interaction. There are extensions of the standard model in which $\alpha$ is dynamical on cosmological length and time-scales. The physics of the cosmic…

Cosmology and Nongalactic Astrophysics · Physics 2019-02-27 Tristan L. Smith , Daniel Grin , David Robinson , Davy Qi

We report the detection of the satellite 18 cm OH lines at 1612 and 1720 MHz in the z=0.2467 molecular absorption system toward the radio source PKS 1413+135. The two OH lines are conjugate; the 1612 MHz line is seen in absorption while the…

Astrophysics · Physics 2009-11-10 Jeremy Darling

Some attempts of easing the critical Hubble tension present in modern cosmology have resorted to using variations of fundamental constants, such as the fine-structure constant, at the time of recombination. In this article we demonstrate…

Cosmology and Nongalactic Astrophysics · Physics 2024-05-22 Léo Vacher , Nils Schöneberg

As is well known, measurements of the Sunyaev-Zeldovich effect can be combined with observations of the X-ray surface brightness of galaxy clusters to estimate the angular diameter distance to these structures. In this paper, we show that…

Cosmology and Nongalactic Astrophysics · Physics 2021-11-01 R. F. L. Holanda , V. C. Busti , L. R. Colaço , J. S. Alcaniz , S. J. Landau

Testing the cosmological variation of fundamental constants of Nature can provide valuable insights into new physics scenarios. While many such constraints have been derived for Standard Model coupling constants and masses, the $\bar\theta$…

High Energy Physics - Phenomenology · Physics 2022-10-13 Hooman Davoudiasl , Julia Gehrlein , Robert Szafron
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