Hafele-keating’s paper gives theoretical formulas and theoretical predictions; In his book General Relativity and Gauge Theory of Gravitation, Professor Duan Yishi, a famous theoretical physicist in China, derived the problem of clocks moving around the Earth from the perspective of general relativity, and made an idealized hypothesis prediction calculation [
6]. In his book Experimental Basis of Special Relativity, Zhang Yuanzhong, a researcher at the Institute of Theoretical Physics of the Chinese Academy of Sciences, also made theoretical derivation and analysis of the round-the-world atomic clock experiment from the perspectives of special relativity and general relativity [
7]. This paper mainly analyzes the theoretical derivation of [
6] and [
7].
2.4.1. Theoretical Derivation and Analysis of [7]
The author divides the time effect of Hafele-Keating experiment into kinematic effect and gravitational effect. The kinematic effect is deduced from the special relativity theory. Gravitational effects are deduced from the perspective of general relativity. All theoretical derivations use of Hafele’s assumptions: “The Earth is assumed to be rotating at an isometric velocity Ω in a non-rotating reference frame Σ.”
The formula of kinematic effect derived from special relativity is:
Note: Formula (01) is come from [
7]p165, formula (9.1.16), and it is a highly approximate relation assuming that the atomic clock moves in the equatorial plane of the Earth with the omission of higher-order terms.
Where: dτ is the proper time interval of an atomic clock traveling eastward around the earth with speed v; dτ0 is the proper time interval of an atomic clock resting on the Earth’s equator. Don’t know why, the authors at this time did not take into account the proper time interval of the atomic clock flying west. Ω is the angular speed of the Earth’s rotation, R is the radius of the Earth’s equator, and c is the speed of light.
The time effect formula derived from general relativity and special relativity is as follows:
Note: Formula (02) is come from [
7]p166, formula (9.1.16), and it is a highly approximate relation assuming that the atomic clock moves in the equatorial plane of the Earth with the omission of higher-order terms.
Where: g is the acceleration of gravity, g=GM/R2; G is the universal gravitational constant, M is the mass of the Earth, and R is the (equatorial) radius of the Earth; Other parameters are the same as formula (01). However, the clock v traveling east takes a positive value, while the clock v traveling west takes a negative value (the author’s original statement is more vague, but in essence this is the case).
Formula (02) can be divided into two parts; The first part is the gravitational effect, which is gh/c2 in formula (02). The second part is the kinematic effect, namely -(v2+2ΩRv)/2c2 in formula (02).
The author did not make a theoretical prediction calculation, but directly cited the [
5] of the theoretical prediction value. According to its theoretical predicted value, due to gravitational effects, the eastbound clock will be 144±14ns faster than the reference clock, the westbound clock will be 179±18ns faster than the reference clock, and the east-west heading clock will be 35ns different. Since [
5] is based on the actual parameters of the east-west voyage, the theoretical calculation and prediction are made. According to the relationship between gravitational effects gh/c
2, It shows that the actual parameters of the east-west distance are different, that is, there is a practical difference between the two parameters gh, which leads to the difference of the east-west heading clock.
Due to kinematic effects, a clock heading east will be 184±23ns slower than the reference clock, a clock heading west will be 96±10ns faster than the reference clock, and the east-west heading clock will differ by 280ns. According to the relationship of kinematic effects -(v2+2ΩRv)/2c2, There are two main reasons for the east-west heading clock difference, one is due to the positive value of the clock v sailing east, and the negative value of the clock v sailing west, resulting in the east-west heading clock difference, which should be the main reason. Second, the actual physical parameters of the east-west voyage are not the same, leading to the difference in the east-west heading clock, which should be a secondary reason.
Researcher Zhang Yuanzhong, despite the detailed derivation of the theoretical relationship between Hafele-Keating experiments and some superficial analysis, wrote a very puzzling paragraph: “When two clocks are traveling in the same circular orbit at an equal speed in opposite directions, even though there is a relative motion between the two clocks, their readings are still the same when the two clocks rejoin.”
This literally means that, in an ideal state, there should be no timing difference when the two clocks flying in opposite directions meet after a week of flying. That is to say, he is well aware that in this matter, relativity has no anisotropy of space and time. If this is the meaning, it is obviously inconsistent with the theoretical relation derived from it; It is also inconsistent with the actual results of the experiment. So there are two possibilities, either the Hafele-Keating experiment doesn’t actually hold up, the experiment is bogus; Or there’s something wrong with relativity. Why, then, did he use the Hafele-Keating experiment as an important experimental basis for verifying the time dilation effect of special relativity?
2.4.2. Theoretical Derivation and Analysis of [6]
The author uses the Schwarzschild metric to derive the time effect relationship of the Hafele-Keating experiment and gets the following results:
Note: Formula (3) is come from [
6]p69, formula (3.298) and (3.299), and it is a highly approximate relation assuming that the atomic clock moves in the equatorial plane of the Earth with the omission of higher-order terms.
Where: T1 is the proper time interval of the reference clock on the ground that is relatively stationary; T2 is the proper time interval of an atomic clock orbiting the Earth at speed v; ω is the angular speed of the earth’s rotation; R is the radius of the Earth’s equator; c is the speed of light; g is the gravitational acceleration, g=GM/R2; G is the universal gravitational constant, M is the mass of the Earth; Similarly, a clock v traveling east takes a positive value, while a clock v traveling west takes a negative value.
Formula (03) looks slightly different from formula (02) on the surface, but with a little adjustment, you will find that the two relations are exactly the same. The authors state that the flight path of the Hafele-Keating experiment is not exactly the same as the conditions used in the derivation of formula (03), but the principle of calculation is exactly the same.
If h=104m and v=300m/s, then:
Under the above ideal conditions, the theoretical reasons for the difference in time of east-west flight clocks are analyzed according to the kinematic and gravitational effects.
In the case of the same g and h parameters, δ
west.gravitation=δ
east.gravitation, that is, gravitational effects are not the theoretical cause of the time difference in the east-west flight clocks.
From the analysis of kinematic effect, even if the parameters of east-west flight clock are completely consistent, the time difference of east-west flight clock will be generated. The core reason is that the clock v traveling east is positive, while the clock v traveling west is negative.