Physics Einstein s relativity problem

First of all, consider the classical view of space-time, that is, Galileo's view of space-time, where time is synchronized between different inertial frames, and there is a simple addition and subtraction relationship between vectors and velocity. In the field of mechanics, there is no difference for the time being, but for the electromagnetic phenomenon, which is a phenomenon about high-speed motion, there is a contradiction in the classical view of space-time, and the wave equation reflects that the propagation speed of electromagnetic waves in a vacuum is the speed of light, but which reference frame is this speed relative to? If we change to another frame of reference, the form of this wave equation will change and does not satisfy the requirements of the covariance of physical laws (i.e., in all inertial frames, physical laws should have the same form, as Newton's laws satisfy).

It was on the basis of this, as well as experiments such as Michelson's measurement of the Earth's motion relative to the ether, that Einstein proposed the theory of relativity, mainly about the establishment of a new view of space-time (i.e., time is no longer a space-independent quantity). The so-called relativity of time, on the one hand, refers to the theory of "moving clock delay" deduced by mathematical expressions, on the other hand, it is still this meaning: the speed of the clock is only relative, if the inertial frame is fixed on the moving clock, the time on the clock is called the inherent time, the time seen by the person moving with the clock is the most essential time, and the person who is fixed on the ground coordinate system will find that the clock slows down.

It can be seen that people located on different frames of reference observe the same clock, and their perception of time will be different, which is not an illusion of people, but a natural essence, an objective fact, and the relativity of time is also reflected here.

It is a theory about space-time and gravity.

Landlord, what the second floor said is right, I'll explain it to you:

In the theory of relativity, time and space are relative, for example: if you say that you have been on the earth for an hour, this has to take a frame of reference, if you choose the earth as the frame of reference, then you have only passed an hour relative to the earth, and there is not an hour relative to the spaceship, maybe 59 minutes.

The theory of relativity assigns the speed of light to the limit speed in the universe, and no object with mass can reach the speed of light, because the mass of an object accelerating to the speed of light is infinite, and the energy required is also infinite.

The speed of time in the theory of relativity is only caused by the difference in the frame of reference, even if you can accelerate you to the speed of light, your time does stop, but you don't feel that your time stops, you don't feel anything else, you feel that you are completely normal.

The third floor also said that "the light you see is the speed of light, but the light itself doesn't think so", and the light will think that you are the speed of light.

The essence lies in the fact that the "relative" landlord still does not understand.

You see light at the speed of light, but light doesn't think so.

This can only explain and describe a theory, but it is not really logical reasoning.

The frame of reference you are talking about is the set of classical mechanics, that is, macroscopic physics. Love is microscopic physics, and it doesn't apply to this!

No, your understanding of the theory of relativity is a bit problematic.

Yes, Einstein's theory of relativity is based on the assumption that the speed of light is absolute, not relative.

This may be abstract, but I'll give you an example, if you have two trains running together, their relative velocity to each other should be 0, right? Okay, at this time, there is a light on the front of one train, so what is the speed of the light seen by the people on the other train? Quite simply, it's the speed of light.

This is easy to understand. The question is, what is the speed of light seen by a person standing on the ground? Should it be the speed of the train plus the speed of light?

Wrong, Einstein told us, or the speed of light. That is, the speed of light is absolute and not under any frame of reference.

Don't ask why, Einstein didn't tell us why, it's like Euclid's axiom that can't be proven. But the theory of relativity is based on this axiom, which is that the speed of light is absolute. Therefore, at a speed close to the speed of light, there is no reference frame at all, and the reference frame is the case of the macroscopic low speed of the object, and the theory of relativity can degenerate into Newtonian mechanics, and then there is a reference frame.

Do you think it's child's play? What he himself could not prove as an axiom? Actually, this is nothing, it can be said that all modern science is based on the axiom system, you can agree with the Euclidean axiom that a line segment can be extended indefinitely, and there is no reason not to agree with the love axiom of the absolute speed of light.

Maybe one day this axiom will prove wrong, that's fine, but for now it's still useful

As already mentioned in senior physics, Einstein was initially faced with two choices, either to deny Maxwell's theory of electromagnetism or to deny the existence of a frame of reference, and Einstein chose the latter. This is one of Einstein's two fundamental assumptions: that all physical laws are the same in different inertial frames of reference.

The other is that the speed of light in a vacuum is the same in different inertial frames of reference, so it's that person who is moving at the speed of light and not you, and you are not moving at the speed of light. All in all, you shouldn't choose him or you as a frame of reference!

The previous netizens have already said the reason, and I am adding:

2.Uniform motion does not encounter this phenomenon, because if you keep moving at a constant speed, you and your friends will never meet, so you must slow down and accelerate and have a U-turn process;

3.General relativity solves this problem, the stronger the gravitational field, the slower the time, and your friend slows down and turns back to the same process as in a gravitational field, so time passes slowly, so he is younger than you.