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The quantum nature of gravity remains one of the greatest mysteries of modern physics, with many unified theories predicting variations in fundamental constants across space and time. Here we present precise measurements of these variations…

Astrophysics of Galaxies · Physics 2025-02-21 Renzhi Su , Tao An , Stephen J. Curran , Michael P. Busch , Minfeng Gu , Di Li

Big Bang Nucleosynthesis (BBN) is very sensitive to the cosmological expansion rate. If the gravitational constant $G$ took a different value during the nucleosynthesis epoch than today, the primordial abundances of light elements would be…

Cosmology and Nongalactic Astrophysics · Physics 2020-03-18 James Alvey , Nashwan Sabti , Miguel Escudero , Malcolm Fairbairn

The recent evidence for a cosmological evolution of the fine structure constant \alpha=e^2/\hbar c found from an analysis of absorption systems in the spectra of distant quasars, is modelled by a cosmological scenario in which it is assumed…

Astrophysics · Physics 2007-05-23 J. W. Moffat

We show that it is possible to steer clear of a spacetime singularity during gravitational collapse by considering the time-variation of a fundamental coupling, in this case, the fine structure constant {\alpha}. We study a spherical…

General Relativity and Quantum Cosmology · Physics 2023-08-08 Soumya Chakrabarti

Light scalar fields very naturally appear in modern cosmological models, affecting such parameters of Standard Model as electromagnetic fine structure constant $\alpha$, dimensionless ratios of electron or quark mass to the QCD scale,…

Atomic Physics · Physics 2009-08-18 V. V. Flambaum , E. V. Shuryak

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

Searching for variations of nature's fundamental constants is a crucial step in our quest to go beyond our current standard model of fundamental physics. If they exist, such variations will be very likely driven by the existence of a new…

Cosmology and Nongalactic Astrophysics · Physics 2023-05-04 Léo Vacher , João F. Dias , Nils Schöneberg , C. J. A. P. Martins , Samy Vinzl , Savvas Nesseris , Guadalupe Cañas-Herrera , Matteo Martinelli

Fundamental physical constants play important role in modern physics. Studies of their variation can open an interface to new physics. An overview of different approaches to a search for such variations is presented as well as possible…

Atomic Physics · Physics 2007-05-23 Savely G. Karshenboim

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

We consider the effect of the coupled variations of fundamental constants on the nucleon magnetic moment. The nucleon g-factor enters into the interpretation of the measurements of variations in the fine-structure constant, alpha, in both…

High Energy Physics - Phenomenology · Physics 2011-12-19 Feng Luo , Keith A. Olive , Jean-Philippe Uzan

We present updated constraints on the variation of the fine structure constant, $\alpha_{\rm EM}$, and effective electron rest mass, $m_{\rm e}$, during the cosmological recombination era. These two fundamental constants directly affect the…

Cosmology and Nongalactic Astrophysics · Physics 2020-05-25 Luke Hart , Jens Chluba

Comparisons between the redshifts of spectral lines from cosmologically-distant galaxies can be used to probe temporal changes in low-energy fundamental constants like the fine structure constant and the proton-electron mass ratio. In this…

Astrophysics · Physics 2010-10-27 Nissim Kanekar

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

The subject of this study is Quantum and Statistical Mechanics of the Early Universe. In it a new approach to investigation of these two theories - density matrix deformation - is proposed. The distinguishing feature of the proposed…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Alex. E. Shalyt-Margolin

Mainly used to set constraints on cosmological parameters, CMB anisotropies can give information on primordial universe. Unfortunately, initial conditions and late time cosmology are degenerated. I focus on the effect of the shape of the…

Astrophysics · Physics 2007-05-23 Marian Douspis

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

There is no doubt that the field of Fundamental Constants in Physics and Their Time Variation is one of the hottest subjects in modern theoretical and experimental physics, with potential implications in all fundamental areas of physics…

High Energy Physics - Phenomenology · Physics 2015-07-14 Joan Solà

We explore the potential variation of two fundamental constants, the fine-structure constant $\alpha$ and the proton-to-electron mass ratio $\mu$, within the framework of modified gravity theories and finite-temperature effects. Utilising…

Solar and Stellar Astrophysics · Physics 2025-09-17 Akhil Uniyal , Surajit Kalita , Yosuke Mizuno , Sayan Chakrabarti , Yan Lu

The Standard Model of particle physics and the theory of General Relativity (GR) currently provide a good description of almost all phenomena of particle physics and gravitation that have received controlled experimental tests. However, the…

Atomic Physics · Physics 2009-01-23 Thomas Dent

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