In Table 1 we present a highly abbreviated list of relative standard uncertainties u r of the physical and chemical fundamental constants most commonly used based on the 20 adjustments, respectively. To date, more than 200 experiments have been performed to precisely determine the value of G, with the latest value recommended by the Committee on Data for Science and Technology (CODATA), named CODATA 2014, having a relative standard uncertainty of 4.7 × 10 −5 in 2016. However, the measurement precision of the gravitational constant has been improved by only about two orders of magnitude in the past two centuries. As is well known, G is one of the earliest fundamental constants introduced by human beings, and it plays a significant role in the fields of theoretical physics, geophysics, astrophysics and astronomy. The strength of this force is defined by the constant of proportionality G, which is called the gravitational constant. This equation describes the attractive force between the two masses M and m separated by the distance r. In this paper we briefly review the history of the G measurement, and introduce eleven values of G adopted in CODATA 2014 after 2000 and our latest two values published in 2018 using two independent methods. This uncertainty is the smallest compared with previous CODATA recommended values of G however, it remains a relatively large uncertainty among other fundamental physical constants. Over the past two decades, eleven precision measurements of the gravitational constant have been performed, and the latest recommended value for G published by the Committee on Data for Science and Technology (CODATA) is (6.674 08 ± 0.000 31) × 10 −11 m 3 kg −1 s −2 with a relative uncertainty of 47 parts per million. ![]() Although G was the first physical constant to be introduced in the history of science, it is considered to be one of the most difficult to measure accurately so far. The Newtonian gravitational constant G, which is one of the most important fundamental physical constants in nature, plays a significant role in the fields of theoretical physics, geophysics, astrophysics and astronomy.
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