Variance of Newtonian constant from local gravitational acceleration measurements

TL;DR

This study uses 22 years of gravitational data to set a new, highly precise upper limit on the variability of Newton's gravitational constant, G, suggesting it is extremely stable over time.

Contribution

It provides the most stringent terrestrial constraints on the variability of G, improving previous limits by four orders of magnitude using gravitational acceleration data.

Findings

Relative variance of G is less than 3×10⁻⁹.

Time variation of G is less than 5.61×10⁻¹⁰ per year.

No intrinsic variation of G detected within measurement accuracy.

Abstract

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 $, this implies the relative variance of Newtonian constant is less than $3\times 10^{-9}$ based on an sine-like oscillation hypothesis. This limit is at least 4 orders of magnitude better than the existing $G$ measurements. The scattered values of reported $G$ measurements coming from different experiments are most probably coming from systematic errors associated with these experiments and not due to intrinsic time variation of $G$. We also find that $\dot{ G} /G<5.61\times 10^{-10} \text{yr}^{-1}$ based on a linear hypothesis. This is the best terrestrial result so far.