Potential energy, its physical essence
One of the most understandable energies is potential energy. It is calculated and transformed by schoolchildren, students and everyone else up to academicians.
Standard definitions of potential energy are something like this:
“Potential energy, part of the total mechanical energy of the system, depending on the relative position of the particles that make up this system, and on their positions in the external force field
“Potential energy is a scalar physical quantity that characterizes the ability of a certain body (or material point) to do work due to its presence in the field of action of forces. Another definition: potential energy is a function of coordinates, which is a term in the Lagrangian of the system, and describes the interaction of the elements of the system. The term “potential energy” was introduced in the 19th century by the Scottish engineer and physicist William Rankin ”. ("Science", Internet).
These are, of course, not entirely accurate definitions. For example, an iron ball falls on an anvil and stops. Where does mechanical energy come from? From potential. And where did the heat energy come from to heat the ball and the anvil? From potential. It turns out that mechanical energy is part of potential energy, and not vice versa. And the large ambiguity in the arrangement of the particles indicates that the definition is not rigorous. You can move the particles as you like along the equipotential surface, without changing anything in their potential capabilities.
The author will not talk about the Lagrangian, since he has no idea about it, and does not believe that the Lagrangian has anything to do with the essence of potential energy.
There is no doubt about the position that the body can perform work, being in the field of action of forces. Indeed, the water falling on the turbine blades does work, and this ability is provided by potential energy.
Potential energy is a very convenient object for mathematical calculations. Much attention is paid to this. For example, Richard Feynman starts straight out by calculating events involving potential energy. His chapters are called: “Chapter 13. Work and potential energy (Ⅰ) ”,“ Heavy work ”, etc. True, there is an article ”Potential energy of gravity” (chapter 4) which gives the following definitions of potential energy:
"... the potential energy of gravity, that is, the energy that the body possesses due to its position in space in relation to the earth." “Potential energy is a general name for energy associated with disposition in relation to something. In this particular case, it is the potential energy of gravitation ”.
These definitions are essentially the same as the TSB definition.
Many people talk about the scale of its countdown. Count it from infinity or from some place, from what magnitude. From zero to some minus or from some positive value to zero, etc. But there is no talk at all about looking for some physical quantity that can be changed so that the potential energy changes. We measure this energy, transform it into kinetic energy, electromagnetic energy, elastic energy, etc. Anyway, we pour something from a bag into a bag, boxes, boxes, etc. And what we pour is unknown - grain, sand, diamonds or something else.
Consider the potential energy of falling water that rotates an electric generator at a hydroelectric power plant. The turbine rotates the generator, but not by itself, but with the help of falling water. Falling water can be represented in the form of balls, which, falling on the plane, move it in the required direction, which rotates the generator. How do they move? Water molecules have an electric negative potential on their outer surface, and there is also such a continuous potential on the turbine blade. Colliding with each other, they share kinetic energy among themselves. The electron of the turbine blade, which received a momentum from the electron of water, tries to move, but since it is connected to the atom, and the atom is connected to other atoms of the turbine shaft up to the generator shaft, it begins to move the shaft and the generator rotor connected to the shaft. As a result of this action, the generator generates electricity that does the required work.
Where did all this come from? What actually happened? The turbine and generator are the same except for wear. If we take a water molecule from a reservoir and a water molecule after passing through a turbine, we find that chemically they are absolutely identical. The amount of water at the inlet and outlet of the hydroelectric station is the same. How did this transformation come about? How does it happen that a barrel of falling water somewhere far away on a river raises the same amount of water into a barrel at the summer cottage of a pensioner near Moscow? Of course, it is easiest to say that the water in the reservoir has potential energy, when the water falls, the potential energy is converted into kinetic energy of water, and this kinetic energy is transferred to the blades of the turbine that rotates the generator, which generates current and further along the chain. All of this is true, but this is a description of the "black box", not its contents.
How is potential energy stored in water? How does it change? This is true, no one knows, and even with incredible hypotheses about this, there are not many. We will briefly outline the vision of this process here. First, let's ask a question - why does the water fall at all? Many people without hesitation will immediately answer: “Gravity ...”, but this answer does not explain anything, because the physics of gravity is not clear. And the physical essence of potential energy can only be explained by understanding the physical essence of gravity. Gravity is interaction photon and resonant to it electron . As long as the water molecule lies on the ground, and with it the electron, nothing special happens, even if there are resonant photons. An electron can absorb this photon, but the speed of the electron must change. The soil does not allow the molecule, and with it the electron, to move. An electron cannot switch to another high-speed regime and therefore cannot hold a given, although it is resonant, photon in its structure. The photon will be emitted. There were no quantum changes in the electron.
But suddenly the support for the molecule is removed. An electron absorbs a photon and receives an impulse towards the photon. With the obtained speed, it should move to the turbine blade, but when the speed zone changes, another resonant structure appears in the electron, which allows the electron to absorb the next resonant photon. And this process is repeated many times along the path of the electron's fall, so it keeps accelerating and accelerating. It gives off its kinetic energy to the turbine blades and decelerates. But it does not slow down to the same speed as in the reservoir. These are the different speeds of the electron relative to the vacuum. Until it is lifted back to the reservoir level (or is involved in some kind of chemical bond), it can never absorb photons of the same energy that it absorbed during the fall. Exactly this amount (the total amount of kinetic energy of absorbed photons) of energy decreased the potential energy of water.
Thus, potential energy is stored in the energy levels of electrons . The larger the spectrum of photons an electron can absorb, the more potential energy it has. Let's just say, the closer the electron was to the nucleus, the more it can absorb photons. The absorption of photons by an electron leads to an increase in its mass. An increase in mass leads to an increase in kinetic energy. Thus, the more water falls from a higher height, the more work it does.
Unfortunately, we cannot yet measure this mass change directly, but we can measure it indirectly, through the change in the size of atoms. The fact that atoms, and, accordingly, all bodies that absorb or emit photons, change their sizes, we observe from the expansion or contraction of bodies when the temperature surrounding these bodies changes. The same happens with any body at speed change .
It is possible that it will be possible to check the changes in the water before and after the turbine. To do this, it is enough to take the same volume of water in the reservoir and after the turbine and count the number of water molecules there and there. It all depends on the ability to carry out this experience. And the complexity of the experiment lies in the fact that a conventional measuring box changes its size when it is transferred from one place to another. The box should be made at the place of measurement, and the yardstick for building the box can be a single quantum (we assume that the quantum does not change its parameters) or a photon, if we are sure that the photon contains both there and there the same number of quanta, that is, portions of energy. The only thing left is to learn how to control photons.
The conclusion is this. Energy in the form of photons is emitted from the Earth (inside it there are many thermal and other photons), turns into kinetic energy in the electrons of water, and the latter is transferred to the turbine. The water that has passed through the turbine is again ready to emit the absorbed spectrum, which it does during evaporation.
And one more thing, approaching the Earth, electrons increase their mass, increasing the size of atoms. The intensity of the movement of atoms and molecules increases, we call this thermal movement. In theory, the most complete electrons and atoms should be in the center of the Earth. And there they should push as much as possible, and pushing, they accelerate each other, forcing to emit photons. These photons propagate both in the Earth itself and throughout space. Such a photon cycle maintains a corresponding temperature mosaic in the Earth. The Earth's core does not heat up or cool down rapidly.