English
Related papers

Related papers: Varying G and Other Constants

200 papers

There are at least three ways in which a varying gravitational constant $G$ could affect the interpretation of the recent high-redhisft Type Ia supernovae results. If the local value of $G$ at the space-time location of distant supernovae…

Astrophysics · Physics 2007-05-23 E. Garcia-Berro , E. Gaztanaga , J. Isern , O. Benvenuto , L. Althaus

This thesis details an effort to generate astrophysically interesting solutions to the two-body problem in General Relativity. The thesis consists of two main parts. The first part presents an analytical variational principle for describing…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Brian D. Baker

We discuss the experimental consequences of hypothetical time variations of the fundamental constants. We emphasize that from a purely phenomenological point of view, only dimensionless fundamental constants have significance. Two classes…

Classical Physics · Physics 2016-09-08 James Rich

Observations indicate that most of the universal matter are invisible and the gravitational constant $G(t)$ maybe depends on the time. A theory of the variational $G$ (VG) is explored in this paper, with naturally producing the useful dark…

Cosmology and Nongalactic Astrophysics · Physics 2015-10-13 Jianbo Lu , Yanfeng Xu , Yabo Wu

We consider an application of precision frequency measurements to searches for possible time variations of the fundamental physical constants. Current laboratory constraints on variations of the fine structure constant alpha and other…

Atomic Physics · Physics 2007-05-23 Savely G. Karshenboim , Victor Flambaum , Ekkehard Peik

The review is devoted to consideration of possible observational consequences of modified gravity theories, suggested for explanation of the contemporary accelerated expansion of the universe. The major attention is paid to F(R)-models. It…

General Relativity and Quantum Cosmology · Physics 2019-11-11 Elena Arbuzova

We use observations related to the variation of fundamental constants, in order to impose constraints on the viable and most used $f(T)$ gravity models. In particular, for the fine-structure constant we use direct measurements obtained by…

General Relativity and Quantum Cosmology · Physics 2017-04-18 Rafael C. Nunes , Alexander Bonilla , Supriya Pan , Emmanuel N. Saridakis

We consider fundamental physical constants which are among a few of the most important pieces of information we have learned about Nature after its intensive centuries-long studies. We discuss their multifunctional role in modern physics…

Atomic Physics · Physics 2014-11-18 Savely G. Karshenboim

Higher-dimensional theories imply that some constants, such as the gravitational constant and the strength of the gauge-couplings, are not fundamental constants. Instead they are related to the sizes of the extra--dimensional space, which…

High Energy Physics - Phenomenology · Physics 2009-11-07 Ph. Brax , C. van de Bruck , A. -C. Davis , C. S. Rhodes

We discuss the various ways in which primordial black holes may have formed in the early Universe and how the effects of such black holes can be used to place constraints on cosmological models. We show that such constraints may be severely…

Astrophysics · Physics 2007-05-23 B. J. Carr , C. A. Goymer

Spacetime-varying coupling constants can be associated with violations of local Lorentz invariance and CPT symmetry. An analytical supergravity cosmology with time-varying fine-structure constant provides an explicit example. Estimates are…

Astrophysics · Physics 2009-09-25 Alan Kostelecky , Ralf Lehnert , Malcolm Perry

It has been pointed out that the value of the gravitational ``constant'' in the early universe may be different from that at present. In that case, it was conjectured that primordial black holes may ``remember'' the value of the…

Astrophysics · Physics 2007-05-23 T. Harada , B. J. Carr , C. A. Goymer

Here, cosmology is obtained from the variable gravitational constant $ G \propto \phi^{-2}$ with $ \phi(x) $ being a scalar and its fluctuations around the ground state. The gravitational action contains Einstein-Hilbert like term with…

General Relativity and Quantum Cosmology · Physics 2008-09-19 S. K. Srivastava

New and rather controversial observations hint that the fine structure constant \alpha may have been smaller in the early universe, suggesting that some of the fundamental ``constants'' of physics may be dynamical. In a recent paper,…

High Energy Physics - Theory · Physics 2010-04-28 S. Carlip , S. Vaidya

We review recent developments in structural stability as applied to key topics in general relativity. For a nonlinear dynamical system arising from the Einstein equations by a symmetry reduction, bifurcation theory fully characterizes the…

General Relativity and Quantum Cosmology · Physics 2025-06-27 Spiros Cotsakis

The variation of fine structure constant with the variation of velocity of light has been studied considering contribution to the permeability and permittivity of the vacuum and incorporating contribution of fractal potential originated…

General Physics · Physics 2017-06-09 A. Bhattacharya , R. Saha , R. Ghosh

I motivate and discuss some recent work on theories with varying constants, and consider some possible observational consequences and tests. Particular emphasis is given to models which can (almost) exactly mimic the predictions of standard…

Astrophysics · Physics 2017-08-23 C. J. A. P. Martins

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

This work describes underlying features of the universe such as fundamental constants and cosmological parameters, conservation laws, baryon and lepton asymmetries, etc. in the context of local gauge theories for fundamental forces under…

High Energy Physics - Phenomenology · Physics 2007-05-23 Heui-Seol Roh

It is well-known that $f(R)$ theories in Einstein frame is conformally equivalent to quintessence models in which the scalar field minimally couples with gravity. If there exists a matter system in Jordan frame, then it interacts with the…

General Relativity and Quantum Cosmology · Physics 2014-11-20 Yousef Bisabr