Photonic or light clocks. Photon box

Photon clocks do not exist in nature, and no one uses them as a clock. Basically, the photon clock is used to explain why and how time slows down when the speed of a body changes in the theory of relativity.

Such a watch has a simple device. These are two parallel reflective planes between which the photon moves.

A photon is reflected from one plane, moves to another, then is reflected from this plane and returns to the first plane. Since the speed of the photon is constant and the distance between the plates is constant, the clock must be fairly accurate. The oscillation period of this clock is equal to the travel time from one mirror to another and back. If the distance between the mirrors is a, then the oscillation period of such a clock is T=2a/c .

Now let's set the clock in motion at the speed of v.

Now the path of the photon will not follow the trajectory b, back and forth, but along the trajectory cc. The path from one reflection surface to another will increase and become equal to a1. Consequently, the oscillation period of the clock will become longer. T1=2а1/c . The clock will run slower - the time has slowed down.

Everything is wonderful. One thing is not clear, with what fright the photon, observing strictly the law of reflection (the angle of incidence is equal to the angle of reflection), suddenly reflected at a different angle different from the angle of incidence. Moreover, it was reflected at an angle just such as to get into the center of another mirror, which flew away for some distance.

Of course, we can say that the photon hitting the point O grabbed the lower mirror and received an additional impulse to the right. As a result of this procedure, the photon must exceed its own speed, which, alas, is impossible. If you start moving such a clock, the photon will go beyond the reflective surfaces and the clock will end.

If you direct the original photon while the clock is moving along the trajectory of cc , then this clock will work as long as it moves uniformly and rectilinearly. As soon as the direction or speed of the clock changes, the photon is immediately lost. A clock without a pendulum is not a clock.

But when speed increases, time slows down? Is the clock slowing down? Yes. But the period of oscillations increases not due to the increase in the path of the photon, but due to the increase in the absorption and emission times of the photon. Until now, we believed that a photon is instantly reflected from a mirror. Rather, they did not even consider, but generally did not pay any attention to this process. Neither Einstein, nor Feynman, nor Green, no one had a question: what happens during the reflection of a photon. And the refractive index shows how much time can be spent on the process of absorption and emission of a photon. And this is all due to the fact that the photon is long - it is a string that scientists cannot find in any way. So as soon as you increased the speed of the clock, the photon began to spend more time on the processes of absorption and emission, and the period of oscillations increased. There is only one subtlety - to accelerate the clock to change the speed it is necessary only during absorption and emission, otherwise the photon will be lost. Who knows what the Coriolis force is, he will understand it right away.

If the photon clock is a mental object, then the photon box is an object realized, as they say, in metal. This box is used to store photons for the purpose of studying and using them. S. Arosh received the Nobel Prize for this in 2012. He outlined these processes in the article “Controlling photons in a box and studying the boundary between quantum and classical”. The article is in the journal Uspekhi fizicheskikh nauk (Volume 184, No. 10).

He used the ENS photon box, which held the photon for up to 170 milliseconds. But this is not a box in the full sense. In a closed box, a photon can be stored for a long time, but this box is open, reminiscent of our clock. And although the mirrors in this box are not flat, but of a special shape, the photon still could not be held in it. The mirrors were 5 centimeters in diameter, and the distance between them was 2.7 centimeters. Perhaps, manipulate the shape and substance of the mirrors, it will be possible to slightly increase the life of a photon in a box, but a very long life of a photon in a box cannot be made. And this cannot be done because the box moves relative to the vacuum, that is, relative to the same as the photon. This is due to the rotation of the Earth around its axis (Coriolis displacement), due to the rotation of the Earth around the Sun, and so on.

In a closed box, a photon can be stored for a long time. It does not go beyond the box, because, having reached the wall, it is again reflected back into the cavity of the box. But such a photon is difficult to work with, there is no extensive access to it. If you make some holes in the box to enter and exit, for example, particles, then the photon will surely fly out through these passages sooner or later.

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