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A sinusoidally time-varying pattern of the values of the Newton's constant of gravitation $G$ measured in Earth-based laboratories over the latest decades has been recently reported in the literature. We put to the test the hypothesis that…

General Relativity and Quantum Cosmology · Physics 2016-01-22 Lorenzo Iorio

There have been recent claims (Anderson et al., EPL, 110, 10002) of a 5.9 year periodicity in measurements of Newton's gravitational constant, $G$, which show a very strong correlation with observed periodic variations in the length of the…

General Relativity and Quantum Cosmology · Physics 2015-09-02 M. Pitkin

Big Bang Nucleosynthesis can provide, via constraints on the expansion rate at that time, limits on possible variations in Newton's Constant, $G$. The original analyses were performed before an independent measurement of the…

Astrophysics · Physics 2009-11-10 Craig J. Copi , Adam N. Davis , Lawrence M. Krauss

We study the variation of the gravitational Newton's constant on cosmological scales in scalar-tensor theories of gravity. We focus on the simplest models of scalar-tensor theories with a coupling to the Ricci scalar of the form $F(\sigma)…

Cosmology and Nongalactic Astrophysics · Physics 2022-06-15 Mario Ballardini , Fabio Finelli , Domenico Sapone

We investigate the variation of the gravitational constant $G$ over the history of the Universe by modeling the effects on the evolution and asteroseismology of the low-mass star KIC 7970740, which is one of the oldest (~11 Gyr) and…

Solar and Stellar Astrophysics · Physics 2020-01-08 Earl Patrick Bellinger , Jørgen Christensen-Dalsgaard

The experimental uncertainties in G between different experiments have important implications for helioseismology. We show that these uncertainties for the standard solar model lead to a range in the value of the square of the sound speed…

Astrophysics · Physics 2009-09-25 Ilidio Lopes , Joseph Silk

We present cosmological constraints on the scalar-tensor theory of gravity by analyzing the angular power spectrum data of the cosmic microwave background obtained from the Planck 2015 results together with the baryon acoustic oscillations…

Cosmology and Nongalactic Astrophysics · Physics 2017-05-09 Junpei Ooba , Kiyotomo Ichiki , Takeshi Chiba , Naoshi Sugiyama

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

We use IGETS absolute gravitational acceleration measurement data to study the gravitational acceleration variance. The relative variance of $\delta g /g$ in 22 years is less than $4\times 10^{-8}$. Since $\delta G /G\lessapprox\delta g /g…

General Relativity and Quantum Cosmology · Physics 2021-04-07 De-Chang Dai

Several properties of the solar interior are determined with a very high accuracy, which in some cases is comparable to that achieved in the determination of the Newton constant $G_N$. We find that the present uncertainty $\Delta…

Astrophysics · Physics 2009-11-07 B. Ricci , F. L. Villante

In spite of two hundred years of considerable efforts directed towards improvement in the experimental techniques, gravitational measurements have provided unsettled results for Newton's gravitational constant G. Analysis of the published…

General Physics · Physics 2007-05-23 V. Raicu

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

A review of different cosmological models in diverse dimensions leading to a relatively small time variation of the effective gravitational constant G is presented. Among them: 4-dimensional general scalar-tensor model, multidimensional…

General Relativity and Quantum Cosmology · Physics 2009-10-29 V. N. Melnikov

About a dozen measurements of Newton's gravitational constant, G, since 1962 have yielded values that differ by far more than their reported random plus systematic errors. We find that these values for G are oscillatory in nature, with a…

General Relativity and Quantum Cosmology · Physics 2015-05-25 John D. Anderson , Gerald Schubert , Virginia Trimble , Michael R. Feldman

Recent high-redshift Type Ia supernovae results can be used to set new bounds on a possible variation of the gravitational constant $G$. If the local value of $G$ at the space-time location of distant supernovae is different, it would…

Astrophysics · Physics 2009-11-07 E. Gaztanaga , E. Garcia-Berro , J. Isern , E. Bravo , I. Dominguez

We analyze the possible variability of the effective Newtonian gravitational constant $G_{\rm N}$ in space and time in the framework of the geometric scalar theory of gravity suggested by M. Novello et al. [JCAP 06, 014 (2013); arXiv:…

General Relativity and Quantum Cosmology · Physics 2020-10-20 K. A. Bronnikov

Most cosmological constraints on modified gravity are obtained assuming that the cosmic evolution was standard $\Lambda$CDM in the past and that the present matter density and power spectrum normalization are the same as in a $\Lambda$CDM…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-22 Laura Taddei , Luca Amendola

Time variation of Newtonian gravitational constant, $G$, is studied in the model universe with variable space dimension proposed recently. Using the Lagrangian formulation of these models, we find the effective gravitational constant as a…

General Relativity and Quantum Cosmology · Physics 2011-08-17 R. Mansouri , F. Nasseri , M. Khorrami

A substantial improvement in the accuracy of G-dot tests (The dot denotes the time derivative.) would make it realistic to speak in terms of a measurement of G-dot, rather than merely a smaller upper bound on |G-dot|. We show that the…

General Relativity and Quantum Cosmology · Physics 2010-11-29 Alvin J. Sanders , George T. Gillies , Ernst Schmutzer

A recent publication (J.D. Anderson et. al., EPL 110, 1002) presented a strong correlation between the measured values of the gravitational constant $G$ and the 5.9-year oscillation of the length of day. Here, we provide a compilation of…

General Relativity and Quantum Cosmology · Physics 2015-06-17 S. Schlamminger , J. H. Gundlach , R. D. Newman
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