What is the gravitational constant, as it is calculated and where is the given value applied

Being one of the fundamental quantities in physics, the gravitational constant was first mentioned in the 18th century. At the same time, the first attempts were made to measure its significance, but due to imperfect devices and insufficient knowledge in this area, it was only possible to do this in the middle of the 19th century. Later the result was repeatedly adjusted (the last time it was done in 2013). However, it should be noted that the principal difference between the first (G = 6.67428 (67) · 10 ^-11 m³ · s ^-2 · kg ^-1 or N · m² · kg ^-2 ) and the last (G = 6.67384 ( 80) · 10 ^-11 m³ · s ^-2 · kg ^-1 or N · m 2 · kg ^-2 ) the values do not exist.

Applying this coefficient for practical calculations, it should be understood that the constant is such in global universal concepts (unless reservations are made to the physics of elementary particles and other little-studied sciences). And this means that the gravitational constant of the Earth, the Moon or Mars will not differ from each other.

This quantity is the basic constant in classical mechanics. Therefore, the gravitational constant participates in a variety of calculations. In particular, without knowing about the more or less accurate value of this parameter, scientists could not calculate such an important factor in the space industry as the acceleration of free fall (which for each planet or other cosmic body will be its own).

However, Newton, who voiced the law of universal gravitation in general form, the gravitational constant was known only in theory. That is, he was able to formulate one of the most important physical postulates, without having information about the magnitude, on which he, in fact, is based.

Unlike other fundamental constants, physics can say only about a certain fraction of accuracy about what the gravitational constant is equal to. Its value is periodically obtained anew, and each time it differs from the previous one. Most scientists believe that this fact is not related to its changes, but to more banal reasons. Firstly, these are measurement methods (various experiments are carried out to calculate this constant), and secondly, the accuracy of the instruments, which gradually increases, the data is refined, and a new result is obtained.

Taking into account the fact that the gravitational constant is a quantity measured 10 to 11 degrees (which is an extremely small value for classical mechanics), there is nothing surprising in the constant refinement of the coefficient. Moreover, the symbol is subjected to correction, beginning with 14 after the decimal point.

However, there is another theory in modern wave physics that Fred Hoyle and J. Narlikar put forward in the 70s of the last century. According to their assumptions, the gravitational constant decreases with time, which affects many other indicators that are considered constants. Thus, the American astronomer van Flandern noted the phenomenon of a slight acceleration of the Moon and other celestial bodies. Guided by this theory, we should assume that there were no global errors in the early calculations, and the difference in the results obtained is explained by changes in the value of the constant itself. The same theory speaks of the inconstancy of certain other quantities, such as the speed of light in a vacuum.