**What can a completely black body tell us?**

An absolutely black body is a body that absorbs all electromagnetic radiation falling on it in all ranges and does not reflect anything. One of these bodies is the Sun. It not only absorbs everything that falls on it, but on the other hand, and radiates what can fall on it. That is, it absorbs all types of radiation that fall on it. They recycle everything that is absorbed and processed and radiate according to their capabilities. If we illuminate the Sun with a flashlight, then it will not reflect the rays of our flashlight, such as a tree or a fence.

The absolutely black body made its feasible contribution to the process of discovering the phenomenon of energy quantization.

As you know, the concept of quantum in science was introduced by Max Planck, based on research on the problem of radiation of an absolutely black body. But did Max Planck draw all the conclusions from this phenomenon while studying the radiation of an absolutely black body?

Scientists have noticed that a completely black body (a ball or box, the inner walls of which are covered with soot, with a small hole) emits and absorbs a certain spectrum of electromagnetic radiation. The intensity of the radiation depends on the temperature of this body. Measurements of the wavelengths of the emitted spectrum and its intensity are presented in the form of curves of red, green and blue colors depending on the temperature in Figure 1.

As you can see from the graph, these curves are, say, not very good for math. It would be good if there was some kind of sine wave, exponent or something else decent. It looks like a Gaussian curve or a bell, but not quite. Rayleigh and Jeans tried to describe this curve and they got the formulas

We got ordinary parabolas with the ** Т ** parameter.
At low frequencies, they are pressed against the abscissa, and at high frequencies, they climb to infinity along the ordinate.
The tail and part of the slope of the real curve were successfully modeled, and the rest of the hump and rise were not described by these formulas.
The curve at high frequencies crept to infinity, which threatened us with an "ultraviolet catastrophe".
Indeed, we could not bear such fluxes of ultraviolet radiation.
And behind ultraviolet radiation of even greater intensity, X-rays would appear.
It was necessary to bend the parabola down at high frequencies.

Max Planck got down to business and picked up a formula that described more accurately experimentally

**is the Plank constant,**

*h***is the Boltzmann constant,**

*k***- frequency.**

*ν*The curves constructed using this formula have the form shown in Figure 2.

As you can see, these curves are very similar to real curves. What is the beauty of this formula?
Let's take any two points on the real curve for one temperature.
Each of these points has a measured intensity and wavelength (frequency).
Let's substitute this data into the Planck formula. We get two equations with two unknowns - ** h ** and

**. All other terms in these equations are known. Having solved these equations, we find the quantities**

*k***and**

*h***. And now, having put these values in the formula, we can theoretically, without measurements, calculate the radiation intensity from the wavelength, or vice versa. The coincidence of theory and practice is obvious.**

*k*Still, Planck was tormented by doubts. Here's what I found on the net about this:

* “Planck suggested that the behavior of light is similar to the movement of a set of many identical harmonic oscillators.
He studied the change in the entropy of these oscillators depending on temperature, trying to substantiate Wien's law, and found a suitable mathematical function for the spectrum of a black body (Planck, 1901). *

* However, soon Planck realized that in addition to his solution, others are possible, leading to different values of the entropy of the oscillators (Planck, 1901).
As a result, he was forced to use, instead of the phenomenological approach, the previously rejected statistical physics (Planck, 1901), which he described as "an act of despair ...
I was willing to sacrifice any of my previous beliefs in physics (Kragh, Helge 1 December 2000, Max Planck: the reluctant revolutionary, PhysicsWorld.com).
One of the new conditions that Planck adopted was:
interpret UN (the vibration energy of N oscillators) not as a continuous infinitely divisible quantity, but as a discrete quantity consisting of the sum of limited equal parts.
Let us denote each such part in the form of an energy element by ?; (Planck, 1901). *

* With this new condition, Planck actually introduced the quantization of the energy of the oscillators, saying that this is "a purely formal assumption ... in fact, I did not think deeply about it ..." (Kragh, Helge 1999, Generations: A History of Physics in the Twentieth Century , Princeton University Press, p. 62, ISBN 0691095523), however, this led to a real revolution in physics.
Applying a new approach to Wien's law of displacement showed that the "energy element" should be proportional to the frequency of the oscillator.
This was the first version of what is now called the "Planck formula":
E=hv*

Max Planck thought brilliantly, and it really made a revolution in physics, but not the kind of revolution that Planck saw. He clearly and unambiguously raised the question:

* “interpret UN (the oscillation energy of N oscillators) not as a continuous infinitely divisible quantity, but as a discrete quantity consisting of the sum of limited equal parts.
Let us denote each such part in the form of an energy element by ?; (Planck, 1901) ”*.

What does this mean? Each oscillator (electron) generates a certain amount of energy, which Planck labeled ?. Where does he get it from? Absorbs thermal energy elements (photons), converts energy into its elements and emits them. Some oscillators emit energy elements with a wavelength of 10,000 A, others with a wavelength of 16,000 A, and so on. As can be seen from the figures, practically this spectrum extends from zero to infinity. Most oscillators generate the wavelength below the top of the bump on the curve. The farther from this hillock, the fewer electrons wanting to generate their photons. Planck suggested that the electron, after the emission of a photon, goes into the energy storage mode (a conventional laser), accumulates energy and emits it again in the form of the same portion, and possibly in the form of another portion. This is not important for the system, because another electron, which had previously emitted another portion of energy, next time will emit a portion that was previously emitted by the previous electron. Thus, UN will be typed as the sum of these portions. The more such portions of energy enter our recorder, the more Intensity we record.

And where does the frequency or wavelength appear here? It does not follow from Planck's proposal that bounded flat parts should follow periodically and, moreover, depend on frequency. It is important that they have the same energy. Perhaps Planck understood that the "elements of energy" cannot depend in any way on the frequency with which they follow each other.

Undoubtedly, there is regularity in radiation, but this is the principle of the organization of radiation, and it consists in the method of imparting certain accelerations to electrons. In experiments with a black body, ordinary body heating is used. The atoms of a substance, usually soot, in the body under the influence of external thermal quanta receive some acceleration, as a result of which they are excited, but do not move to a new stationary orbit in an equilibrium state, but emit a certain photon. If the temperature is changed, then the equilibrium is violated, and some of the electrons will be transferred to the next stable level, and a new spectrum will emit relative to it.

All electrons of the body are distributed at different speeds. The bound electrons are at different levels depending on the degree of connectivity and they have different speeds. All other things being equal, electrons, depending on these velocities, can emit photons of one or another energy. With a change in temperature, the average speed of the oscillators changed, and, accordingly, the hump of the curve crept behind this change. The figures show the displacement of the hillock to the high frequency region.

Naturally, Planck, having broken the continuous radiation of oscillators into identical pieces (energy elements), made a tremendous step in science, but his followers managed to obscure the whole matter and lead science somewhat in the wrong direction. Why is that? When Planck broke the radiation, he got two frequencies. Figure 3.

The repetition rates of these "energy elements" appeared: ?1 and ?2. And, as everyone believed, there were also frequencies in the "energy elements" themselves with wavelengths: ?3 and ?4. These frequencies were originally in continuous radiation, which Planck tore apart. And it just so happened that the measured radiation intensity coincided with the repetition rate of these "energy elements", which corresponded to the formula:

In fact, in order not to obscure the essence of the phenomenon, instead of the frequency

**, the symbol**

*ν***or instead of**

*k***(energy) the symbol**

*E***(intensity). In this case, the concept of quantum energy and radiation will be differentiated. More can be found in the article "Electromagnetic radiation" . There is one phenomenon on the charts that for some reason no one paid attention to. Namely. Why is the hump of the curve in the wavelength range of approximately 500-800 nm, and not in the range of 100-400 nm or 1200-1500 nm? And this is one more confirmation of the existence of our quantum world. Из этого следует, что средняя скорость нашего мира относительно вакуума именно такова, что генерируются в основном фотоны такой длины. Naturally, deviations of the electron velocity from this average velocity lead to the generation of various photons. And the greater the deviation of the velocity from the average value, the less often it occurs, and the less the intensity of this radiation. If our world acquired a different speed, different from the real speed, then the hump of the curve would shift by the corresponding amount. Basically around this average speed, electrons would absorb and emit corresponding photons. And since in each speed zone the constant component in each of the photons is different, then the time of generation or transfer of photons is different. And this is nothing but physical essence of time . An outside observer, seeing two IRFs with humps at different wavelengths, would find that people move slower in one IRF than in the other.**

*UN*Whether the author of these lines made the correct addition to the interpretation of the essence of the radiation curve, time will tell, but the derivation of the dependence of the energy of a quantum on its frequency, made through Wien's displacement law, is not accurate. A quantum is one smallest particle of energy and it contains certain movements of the electrical and magnetic components, but these oscillations, if any in a quantum, are the same, otherwise quantum will be unstable, that is, it will not be able to exist. But photon it is a set of identical quanta. And the total photon energy depends on the sum of all quanta. These quantized sets (photons) make up the sum of UN.

And one more fantastic conclusion can be drawn from the radiation curve. If part of the substance of our universe had a different average speed, which is possible when two universes intersect, then this could be called a parallel world. The photons of one world would practically not interact with bodies of the opposite world and could coexist side by side And they would appear only in the form of UFOs, when the tail or the beginning of the radiation curve of an absolutely black body in one IFR fell into the zone of the hillock of the curve of another IFR. It could be like that. Suppose in some world the curve will have a hump in the region of medium radio waves or in the region of X-rays. If medium wavelengths try to generate a visible spectrum, just as we are now generating an X-ray spectrum, or detonate an atomic bomb, then we can see the visible spectrum in the form of some object. But those who live in the X-ray zone will also see our tricks, because there is a lot of X-rays in the explosion.

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