The English information on the principle of invariance of the speed of light, the principle of invar

The principle of invariance of the speed of light is one of the two basic assumptions of special relativity, in which it means that the propagation speed of light in a vacuum is a constant relative to the observer, regardless of the inertial frame of reference in which it is observed, and does not change with the relative motion of the light source and the observer's frame of reference. This value is 299,792,458 meter seconds.

The principle of invariance of the speed of light was obtained by solving Maxwell's equations simultaneously and confirmed by the Michelson-Morey experiment. The principle of invariance of the speed of light is one of the basic starting points for Einstein's creation of the special theory of relativity.

In the general theory of relativity, since the so-called inertial frame of reference no longer exists, Einstein introduced the principle of general relativity, that is, the form of the laws of physics is constant in all frames of reference, which also makes the principle of the invariance of the speed of light applicable to all frames of reference.

However, all kinds of experiments that do not change the speed of light can only prove that the speed of light does not change in the loop, and have never been able to prove that the speed of light in one direction does not change, and even regard the speed of light in one direction as an unobservable quantity. Therefore, the principle of invariance of the speed of light is still a hypothesis to be proven [1].

English is harder to find, but you can refer to here for detailed information on the speed of light.

a ?The principle of invariance of the speed of light, in the special theory of relativity, refers to the fact that the propagation speed of light in a vacuum is a constant regardless of the inertial frame (inertial frame of reference) in which it is observed, and does not change with the relative motion of the light source and the frame of reference in which the observer is located. This value is 299,792,458 meter seconds.

The principle of invariance of the speed of light was obtained by solving Maxwell's equations simultaneously and confirmed by the Michelson-Morey experiment. The principle of invariance of the speed of light is one of the basic starting points for Einstein's creation of the special theory of relativity.

In the general theory of relativity, since the so-called inertial frame of reference no longer exists, Einstein introduced the principle of general relativity, that is, the form of the laws of physics is constant in all frames of reference. This also allows the principle of invariance of the speed of light to be applied to all reference frames.

The principle of invariance of the speed of light is referred to as follows:

The speed of light is constant at three levels The speed of propagation of light in the same medium remains the same The speed of propagation of light in different media is different, but this is not to say that the propagation of light requires them as a medium, just to express that through light between them, the propagation of light does not require any medium), such as traveling in a vacuum, the fastest speed in air, water, glass, and slower, but the propagation speed of light in the same medium is constant, which is determined by the law of electromagnetism.

We now know that light is an electromagnetic wave, so light must also follow Maxwell's equations, from which it is easy to derive the speed of light (electromagnetic wave velocity). is the permittivity, is the permeability, they are fixed in the same medium, from here it is also easy to see that the speed of light is a constant in the same medium, it is only related to the permittivity and permeability. The speed of light does not change with the movement of the Luminous Finger source.

It's easy to understand that the speed of light doesn't change with the movement of a light source, but it's not just electromagnetic waves of light, but also our ordinary water waves. Axioms are things that can't be proven right or wrong, and you have to accept them if you want to play them. There are many theoretical systems in mathematics, and you can come up with some axioms on your own.

Then derive some useful theorems from these axioms, but you have to make sure that the system you build is self-consistent, and to put it simply, you have to be categorical, don't be deduced by one theorem that your system says that the triangle is 180 degrees, and the other theorem says that the angles of the triangle add up to 240 degrees, so that your theory is completely finished.

Analysis: If there is a beam of light in the k system propagating with velocity c in a certain direction (here you might as well take the x-axis direction), i.e., v = c, then the Lorentz velocity transformation formula is used. The propagation velocity of this beam in k is v = i.e., the speed of light in a vacuum observed in other inertial frames is also c in accordance with the principle of invariance of the speed of light.