Special or partial theory of relativity is a theory of the structure of space-time. It was first introduced in 1905 by Albert Einstein in his work “On the Electrodynamics of Moving Bodies.” The theory describes motion, the laws of mechanics, and the space-time relationships that define them, at motion speeds close to the speed of light. Classical Newtonian mechanics within the framework of special relativity is an approximation for low speeds.
General theory of relativity
General relativity is a theory of gravity developed by Einstein in 1905-1917. It is a further development of the special theory of relativity. The general theory of relativity postulates that gravitational effects are caused not by the force interaction of bodies and fields, but by the deformation of the space-time itself in which they are located. This deformation is related, in part, to the presence of mass-energy.
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- General theory of relativity - space-time continuum (Russian) - Simply about the complex.
- Special theory of relativity (Russian) - Simply about the complex.
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Books
- Physics of high-current relativistic electron beams, A. A. Rukhadze, L. S. Bogdankevich, S. E. Rosinsky, V. G. Rukhlin. The fundamentals of the physics of pulsed high-current electron beams and their interaction with plasma are systematically presented. Various equilibrium configurations, formation and...
Special theory of relativity(SRT) considers the relationship of physical processes only in inertial reference systems (FR), that is, in FRs that move relative to each other uniformly in a straight line.
General theory of relativity(GR) considers the interrelationship of physical processes in non-inertial CO, that is, in CO that are moving at an accelerated pace relative to each other.
Space
characterizes the relative position of bodies;
space is homogeneous, has three dimensions;
all directions in space are equal.
Time
characterizes the sequence of events;
time has one dimension;
time is homogeneous and isotropic.
Postulates of the theory of relativity:
1. In all inertial reference frames, all physical phenomena occur in the same way.
Those. all inertial references equal rights. No experiments in any field of physics make it possible to isolate the absolute inertial CO.
2. The speed of light in vacuum is the same in all inertial references and does not depend on the speed of the light source and the observer (i.e. the speed of light in a vacuum is invariant).
The speed of light propagation in a vacuum is maximum possible the speed of propagation or transmission of any interaction:
s = 299792.5 km/s.
The relativity of simultaneity
Event is any phenomenon occurring at a given point in space at a certain point in time.
To set an event means to set a point in the four-dimensional space “coordinates - time”, i.e. when and where the event occurs.
In classical mechanics Newton's time is the same in any inertial reference frame, that is, it has an absolute value and does not depend on the choice of CO.
In relativistic mechanics time depends on the choice of CO.
Events occurring simultaneously in one SO may not be simultaneous in another SO moving relative to the first.
Regarding two clocks, one of which is located at the bow and the other at the stern of the ship, the event (flare) does not occur simultaneously. Clocks A and B are synchronized and are at the same distance from the light source located between them. Light travels at the same speed in all directions, but the watch detects the flash at different times.
Let one observer be inside the ship (internal observer) in the reference frame K’, and the second outside the ship (external observer) in the reference frame K.
The reference system K' is connected to the ship and moves at speed v
relatively stationary reference system K, which associated with an external observer.
If in the middle of a ship that is moving at some speed v relative to the external observer, the light source will flash, then for the internal observer the light reaches the stern and bow of the ship at the same time. Those. in the reference frame K' these two events occur simultaneously.
For an external observer, the stern will “approach” the light source, and the bow of the ship will move away, and the light will reach the stern before the bow of the ship. Those. in the reference frame K these two events do not occur simultaneously.
Relativistic law of addition of velocities
The classical law of addition of velocities cannot be applied in relativistic mechanics (this contradicts the second postulate of SRT), therefore the relativistic law of addition of velocities is used in STR.
It is obvious that at speeds that are much less than the speed of light, the relativistic law of addition of velocities takes the form of the classical law of addition of velocities.
Consequences of the postulates of the theory of relativity
1. Time intervals increase, time slows down.
Time dilation has been experimentally demonstrated during the radioactive decay of nuclei: the radioactive decay of accelerated nuclei is slowed down compared to the radioactive decay of the same nuclei at rest.
2. The sizes of bodies decrease in the direction of movement.
From the formula it is clear that the body has the greatest length in a stationary CO. The change in body length during movement is called Lorentzian contraction of length .
How are mass and energy related?
In the literature, Einstein’s famous formula is written in 4 versions, which indicates that it is not very deeply understood.
The original formula appeared in a short note by Einstein in 1905:
This formula has a deep physical meaning. She says that The mass of a body that is at rest as a whole determines the energy content in it, regardless of the nature of this energy.
For example, the internal kinetic energy of the chaotic movement of the particles that make up the body is included in the rest energy of the body, in contrast to the kinetic energy of translational motion. That is, by heating a body, we increase its mass.
It should also be noted that the formula is read from right to leftAny mass determines the energy of a body. But not every energy can be put in correspondence with some mass.
It also follows from the formula that
the change in the energy of a body is directly proportional to the change in its mass:
In the case when the body begins to move, the rest energy turns into total energy in CO, which moves forward as a whole at a certain speed v .
Relativistic mechanics is the mechanics into which Newtonian mechanics turns if a body moves at a speed close to the speed of light. At such high speeds, simply magical and completely unexpected things begin to happen to things, such as, for example, relativistic length contraction or time dilation.
But how exactly does classical mechanics become relativistic? About everything in order in our new article.
Let's start from the very beginning...
Galileo's principle of relativity
Galileo's principle of relativity (1564-1642) states:
In inertial reference systems, all processes proceed in the same way if the system is stationary or moves uniformly and rectilinearly.
In this case we are talking exclusively about mechanical processes. What does it mean? This means that if we, for example, sail on a uniformly and rectilinearly moving ferry through fog, we will not be able to determine whether the ferry is moving or at rest. In other words, if you conduct an experiment in two identical closed laboratories, one of which moves uniformly and rectilinearly relative to the other, the result of the experiment will be the same.
Galilean transformations
Galilean transformations in classical mechanics are transformations of coordinates and velocity when moving from one inertial reference system to another. We will not present all the calculations and conclusions here, but simply write down the formula for converting speed. According to this formula, the speed of a body relative to a stationary frame of reference is equal to the vector sum of the speed of the body in a moving frame of reference and the speed of the moving frame of reference relative to a stationary frame.
The Galilean principle of relativity we cited above is a special case of Einstein’s principle of relativity.
Einstein's principle of relativity and postulates of SRT
At the beginning of the twentieth century, after more than two centuries of dominance of classical mechanics, the question arose of extending the principle of relativity to non-mechanical phenomena. The reason for this question to arise was the natural development of physics, in particular optics and electrodynamics. The results of numerous experiments either confirmed the validity of the formulation of Galileo's principle of relativity for all physical phenomena, or in a number of cases indicated the fallacy of Galileo's transformations.
For example, checking the formula for adding velocities showed that it is incorrect at velocities close to the speed of light. Moreover, Fizeau's experiment in 1881 showed that the speed of light does not depend on the speed of movement of the source and the observer, i.e. remains constant in any frame of reference. This experimental result did not fit into the framework of classical mechanics.
Albert Einstein found a solution to this and other problems. In order for theory to converge with practice, Einstein had to abandon several seemingly obvious truths of classical mechanics. Namely, to assume that distances and time intervals in different reference systems are not constant . Below are the main postulates of Einstein’s Special Theory of Relativity (STR):
First postulate:In all inertial frames of reference, all physical phenomena proceed in the same way. When moving from one system to another, all the laws of nature and the phenomena that describe them are invariant, that is, no experiments can give preference to one of the systems, because they are invariant.
Second postulate : With the speed of light in a vacuum is the same in all directions and does not depend on the source and the observer, i.e. does not change when moving from one inertial frame to another.
The speed of light is the maximum speed. No signal or action can travel faster than the speed of light.
Transformations of coordinates and time during the transition from a stationary reference system to a system moving at the speed of light are called Lorentz transformations. For example, let one system be at rest, and the second move along the abscissa axis.
As we see, time also changes along with the coordinates, that is, it acts as a quarter coordinate. Lorentz transformations show that in STR space and time are inseparable, unlike classical mechanics.
Remember the paradox of two twins, one of whom was waiting on the ground, and the second was flying in a spaceship at very high speed? After the astronaut brother returned to earth, he found his brother an old man, although he himself was almost as young as when the journey began. A typical example of how time changes depending on the reference system.
At speeds much lower than the speed of light, the Lorentz transformations turn into Galilean transformations. Even at the speed of modern jets and rockets, deviations from the laws of classical mechanics are so small that they are practically impossible to measure.
Mechanics that takes into account Lorentz transformations is called relativistic.
Within the framework of relativistic mechanics, the formulations of some physical quantities change. For example, the momentum of a body in relativistic mechanics in accordance with the Lorentz transformations can be written as follows:
Accordingly, Newton's second law in relativistic mechanics will have the form:
And the total relativistic energy of a body in relativistic mechanics is equal to
If the body is at rest and the speed is zero, this formula is transformed into the famous
This formula, which everyone seems to know, shows that mass is a measure of the total energy of a body, and also illustrates the fundamental possibility of converting the energy of matter into radiation energy.
Dear friends, on this solemn note we will end our review of relativistic mechanics today. We looked at the principle of relativity of Galileo and Einstein, as well as some basic formulas of relativistic mechanics. We remind those who are persistent and have read the article to the end that there are no “unsolvable” tasks or problems in the world that cannot be solved. There is no point in panicking and worrying about unfinished coursework. Just remember the scale of the Universe, take a deep breath and entrust the task to real professionals -
Used in physics for phenomena caused by movement at speeds close to the speed of light or strong gravitational fields. Such phenomena are described by the theory of relativity.
Modern encyclopedia. 2000 .
Synonyms:See what "RELATIVISTIC" is in other dictionaries:
Relativistic Dictionary of Russian synonyms. relativistic adj., number of synonyms: 1 relativistic (1) Dictionary sinon ... Synonym dictionary
RELATIVISTIC, relativistic, relativistic (philosophical, scientific). adj. to relativist. Ushakov's explanatory dictionary. D.N. Ushakov. 1935 1940 ... Ushakov's Explanatory Dictionary
RELATIVISM, a, m. In philosophy: methodological position, supporters of the swarm, absolutizing the relativity and conditionality of all our knowledge, consider objective knowledge of reality impossible. Ozhegov's explanatory dictionary. S.I. Ozhegov, N.Yu.... ... Ozhegov's Explanatory Dictionary
Adj. 1. ratio with noun relativism, relativist, associated with them 2. Characterized by relativism, associated with A. Einstein’s theory of relativity. Ephraim's explanatory dictionary. T. F. Efremova. 2000... Modern explanatory dictionary of the Russian language by Efremova
Relativistic, relativistic, relativistic, relativistic, relativistic, relativistic, relativistic, relativistic, relativistic, relativistic, relativistic, relativistic, relativistic, relativistic, relativistic,... ... Forms of words
- (lat. relativus relative) physical. term relating to phenomena considered on the basis of special. (particular) theory of relativity (the theory of the movement of bodies with velocities close to the speed of light) or based on the general theory of relativity (theory ... Dictionary of foreign words of the Russian language
relativistic- relativistic… Russian spelling dictionary
relativistic - … Spelling dictionary of the Russian language
Aya, oh. 1. to Relativism and Relativist. R views, beliefs. Paradise theory of knowledge. 2. Phys. Relating to phenomena considered on the basis of the theory of relativity. Paradise particle. Extreme speed (close to the speed of light) ... encyclopedic Dictionary
relativistic- oh, oh. 1) to relativism and relativist. R views, beliefs. Paradise theory of knowledge. 2) physical Relating to phenomena considered on the basis of the theory of relativity. Paradise particle. Extreme speed (close to the speed of light) ... Dictionary of many expressions
Books
- The structure of space-time, R. Penrose. The author's name is well known to theoretical physicists and cosmologists. It was Penrose who proved the important theorem about the inevitability of the emergence of a physical singularity of space-time...
Physics and reductionism. Physics and visibility. Theory of relativity.
Physics and reductionism
In this topic we will give a snapshot of the modern structure of the world. One of the most ancient and fundamental sciences - physics - will help us. Physics is the most important of the natural sciences, since literally translated from Greek, the word “physics” means “nature”. Therefore, physics is the science of nature. Physics has always been considered the standard of scientific knowledge. In what sense? Not that it provides the most important and true knowledge, but that it reveals truths that are valid for the entire Universe about the relationship of several basic variables. Its versatility is inversely proportional to the number of variables it introduces into its formulas.
Just as atoms and quarks are the “building blocks” of the universe, so the laws of physics are the “building blocks” of knowledge. The laws of physics are the “building blocks” of knowledge not only because they use some basic and universal variables and constants that operate throughout the Universe, but also because the principle of reductionism operates in science, which states that more and more complex laws for the development of more complex levels of reality must be reducible to the laws of simpler levels.
For example, the laws of reproduction of life in genetics are revealed at the molecular level as the laws of interaction between DNA and RNA molecules. Coordination of the laws of various areas of the material world is carried out by special frontier sciences, such as molecular biology, biophysics, biochemistry, geophysics, geochemistry, etc. Very often, new sciences are formed precisely at the junctions of more ancient disciplines.
There are fierce debates regarding the scope of applicability of the principle of reductionism in the methodology of science, but the explanation itself always presupposes the reduction of the explained to a lower conceptual level. In this sense, science simply confirms its rationality.
Physicists claim that not a single body in the Universe can disobey the law of universal gravitation, and if its behavior contradicts this law, then other laws intervene. The plane does not fall to the ground due to its design and engine. A spaceship overcomes gravity due to jet fuel, etc. Neither an airplane nor a spaceship denies the law of gravity, but uses factors that neutralize its effect.
You can deny the laws of philosophy, religion, mystical miracles, and this is considered normal. But they look with suspicion at a person who denies the laws of science, say, the law of universal gravitation. In this sense, we can say that the laws of physics lie at the basis of the scientific understanding of reality.
Physics and visualization
Two circumstances make it difficult to understand modern physics. Firstly, the use of a complex mathematical apparatus, which must first be studied. A. Einstein made a successful attempt to overcome this difficulty by writing a textbook that did not contain a single formula. But there is another circumstance that turns out to be insurmountable - the impossibility of creating a visual model of modern physical concepts: curved space; a particle that is also a wave, etc. The way out of the situation is simple - there is no need to even try to do it.
The progress of physics (and science in general) is associated with a gradual abandonment of direct visibility. As if such a conclusion should contradict the fact that modern science and physics are primarily based on experiment, that is, empirical experience that takes place under human-controlled conditions and can be reproduced at any time any number of times. But the whole point is that some aspects of reality are invisible to superficial observation and clarity can be misleading. Aristotle's mechanics was based on the principle: “A moving body stops if the force pushing it ceases to act.” It turned out to correspond to reality simply because it was not noticed that the reason the body stops is friction. In order to draw the correct conclusion, an experiment was required, which was not a real experiment, impossible in this case, but an ideal experiment.
Such an experiment was carried out by the great Italian scientist Galileo Galilei, author of the “Dialogue on the Two Chief Systems of the World, Ptolemaic and Copernican” (1632). In order for this thought experiment to become possible, it was necessary to imagine an ideally smooth body and an ideally smooth surface that eliminates friction. Galileo's experiment, which led to the conclusion that if nothing influences the motion of a body, it can continue indefinitely, became the basis of Newton's classical mechanics (remember the three laws of motion from the school physics curriculum). In 1686, Isaac Newton presented his “Mathematical Principles of Natural Philosophy” to the Royal Society of London, in which he formulated the basic laws of motion, the law of universal gravitation, the concepts of mass, inertia, and acceleration. Thus, thanks to thought experiments, a new mechanistic picture of the world became possible.
Perhaps Galileo’s famous thought experiments were inspired by the creation of a heliocentric system of the world by the outstanding Polish scientist Nicolaus Copernicus (1473-1543), which became another example of the rejection of direct visibility. Copernicus's major work, On the Conversion of the Celestial Worlds, summarized his observations and reflections on these issues for more than 30 years. The Danish astronomer Tycho Brahe (1546-1601), for the sake of clarity, put forward a hypothesis in 1588 according to which all the planets rotate around the Sun with the exception of the Earth, the latter is motionless and the Sun with the planets and the Moon revolve around it. And only Johannes Kepler (1571-1630), having established three laws of planetary motions bearing his name (the first two in 1609, the third in 1618), finally confirmed the validity of the teachings of Copernicus.
So, the progress of modern science was determined by idealized ideas that broke with immediate reality. However, the physics of the 20th century forces us to abandon not only direct visibility, but also visibility as such. This prevents the representation of physical reality, but allows us to better understand the truth of Einstein’s words that “physical concepts are free creations of the human mind and are not uniquely determined by the external world” (Einstein A., Infeld L. Evolution of Physics. - P. 30). “In our quest to understand reality, we are partly like a person who wants to understand the mechanism of a closed clock. He sees the dial and the moving hands, even hears the ticking, but has no means of opening their case. If he is witty, he can draw himself a certain picture of the mechanism that would correspond to everything that he observes, but he can never be completely sure that his picture is the only one that could explain his observations. . thirty).
Refusal of the clarity of scientific ideas is an inevitable price to pay for the transition to the study of deeper levels of reality that do not correspond to the evolutionarily developed mechanisms of human perception.
Theory of relativity
Even in classical mechanics, Galileo’s principle of relativity was known: “If the laws of mechanics are valid in one coordinate system, then they are valid in any other system moving rectilinearly and uniformly relative to the first” (Einstein A., Infeld L. Evolution of physics. - S. 130). Such systems are called inertial, since the movement in them is subject to the law of inertia, which states: “Every body maintains a state of rest or uniform rectilinear motion, unless it is forced to change it under the influence of driving forces” (Ibid. - P. 126).
At the beginning of the 20th century, it became clear that the principle of relativity is also valid in optics and electrodynamics, that is, in other branches of physics. The principle of relativity expanded its meaning and now sounded like this: any process proceeds equally in an isolated material system and in the same system in a state of uniform rectilinear motion. Or: the laws of physics have the same form in all inertial frames of reference.
After physicists abandoned the idea of the existence of the ether as a universal medium, the idea of a reference frame of reference also collapsed. All reference systems were recognized as equivalent, and the principle of relativity became universal. Relativity in the theory of relativity means that all reference systems are the same and there is no one that has advantages over others (relative to which the ether would be motionless).
The transition from one inertial system to another was carried out in accordance with Lorentz transformations. However, experimental data on the constancy of the speed of light led to a paradox, the resolution of which required the introduction of fundamentally new concepts.
The following example will help explain this. Let us assume that we are sailing on a ship moving rectilinearly and uniformly relative to the shore. All the laws of movement remain the same here as on the shore. The overall speed of movement will be determined by the sum of the movement on the ship and the movement of the ship itself. At speeds far from the speed of light, this does not lead to a deviation from the laws of classical mechanics. But if our ship reaches a speed close to the speed of light, then the sum of the speed of movement of the ship and on the ship may exceed the speed of light, which in fact cannot be, since according to the Michelson-Morley experiment, “the speed of light is always the same in all systems coordinates, regardless of whether the emitting source is moving or not, and regardless of how it moves” (Einstein A., Infeld L. Cited. - P. 140).
Trying to overcome the difficulties that arose, in 1904 H. Lorenz proposed to consider that moving bodies contract in the direction of their movement (and the contraction coefficient depends on the speed of the body) and that apparent time intervals are measured in different reference systems. But the following year, A. Einstein interpreted apparent time in Lorentz transformations as true.
Like Galileo, Einstein used a thought experiment called the Einstein Train. “Let us imagine an observer riding on a train and measuring the speed of light emitted by the street lights on the side of the road, i.e., moving at speed C in a reference frame relative to which the train is moving at speed V. According to the classical theorem of addition of velocities, an observer traveling on a train would have to attribute the speed C - V to the light propagating in the direction of the train's movement." (Prigozhy I., Stengers I. Order from chaos. - P. 87). However, the speed of light acts as a universal constant of nature.
Considering this contradiction, Einstein proposed abandoning the idea of the absoluteness and immutability of the properties of space and time. This conclusion contradicts common sense and what Kant called the conditions of intuition, since we cannot imagine any space other than three-dimensional, and no time other than one-dimensional. But science does not necessarily have to follow common sense and unchanging forms of sensibility. The main criterion for it is the correspondence between theory and experiment. Einstein's theory met this criterion and was accepted. At one time, the idea that the Earth was round and moved around the Sun also seemed contrary to common sense and observation, but they turned out to be true.
Space and time have traditionally been considered in philosophy and science as the main forms of existence of matter, responsible for the location of individual elements of matter relative to each other and for the natural coordination of successive phenomena. The characteristics of space were considered uniformity- identical properties in all directions, and isotropy- independence of properties from direction. Time was also considered homogeneous, i.e., any process is, in principle, repeatable after a certain period of time. Associated with these properties is the symmetry of the world, which is of great importance for its knowledge. Space was viewed as three-dimensional, and time as one-dimensional and moving in one direction - from the past to the future. Time is irreversible, but in all physical laws nothing changes from changing the sign of time to the opposite one, and therefore physically the future is indistinguishable from the past.
In the history of science, two concepts of space are known: unchanging space as a container of matter (Newton’s view) and space, the properties of which are associated with the properties of the bodies located in it (Leibniz’s view). According to the theory of relativity, any body determines the geometry of space.
From the special theory of relativity it follows that the length of a body (in general, the distance between two material points) and the duration (as well as the rhythm) of the processes occurring in it are not absolute, but relative quantities. When approaching the speed of light, all processes in the system slow down, the longitudinal (along the movement) dimensions of the body are reduced, and events that are simultaneous for one observer turn out to be different in time for another, moving relative to him. “The rod will shrink to zero if its speed reaches the speed of light... the clock would completely stop if it could move at the speed of light” (Einstein A., Infeld L. Cited. - P. 158).
It has been experimentally confirmed that a particle (for example, a nucleon) can manifest itself in relation to a particle moving slowly relative to it as a spherical particle, and in relation to a particle incident on it at a very high speed - as a disk flattened in the direction of movement. Accordingly, the lifetime of a slowly moving charged pi meson is approximately 10~8 sec, and that of a rapidly moving one (at near-light speed) is many times longer. So, space and time are general forms of coordination of material phenomena, and not independently existing independently of the matter of the beginning of being.
The combination of Galileo's principle of relativity with the relativity of simultaneity, found by Einstein, was called the Einstein principle of relativity. The concept of relativity has become one of the main ones in modern natural science.
In the special theory of relativity, the properties of space and time are considered without taking into account gravitational fields, which are not inertial. General relativity extends the laws of nature to everything, including non-inertial systems. The general theory of relativity linked gravity with electromagnetism and mechanics. She replaced Newton's mechanistic law of universal gravitation with the field law of gravitation. “Schematically, we can say: the transition from Newton’s law of gravitation in general relativity is to some extent analogous to the transition from the theory of electrical fluids and Coulomb’s law to Maxwell’s theory” (Einstein A., Infeld L. Cited. - P. 196). And here physics moved from matter theory to field theory.
For three centuries, physics was mechanistic and dealt only with matter. But “Maxwell’s equations describe the structure of the electromagnetic field. The arena of these laws is the entire space, and not just the points at which matter or charges are located, as is the case for mechanical laws” (Ibid. - P. 120). The concept of field defeated mechanism.
Maxwell's equations “do not relate, as Newton's laws do, two widely separated events; they do not relate events here to conditions there. The field here and now depends on the field in the immediate neighborhood at the moment that has just passed” (Ibid. - P. 120). This is a significantly new moment in the field picture of the world. Electromagnetic waves travel at the speed of light in space and the gravitational field acts in a similar way.
Masses that create a gravitational field, according to the general theory of relativity, bend space and change the flow of time. The stronger the field, the slower time flows compared to the passage of time outside the field. Gravity depends not only on the distribution of masses in space, but also on their movement, on the pressure and tension present in bodies, on electromagnetic and all other physical fields. Changes in the gravitational field are distributed in a vacuum at the speed of light. In Einstein's theory, matter influences the properties of space and time.
When moving to cosmic scales, the geometry of space ceases to be Euclidean and changes from one region to another depending on the density of masses in these regions and their movement. On the scale of a metagalaxy, the geometry of space changes over time due to the expansion of the metagalaxy. At speeds approaching the speed of light, with a strong field, space comes to a singular state, that is, it is compressed into a point. Through this compression, the megaworld comes into interaction with the microworld and in many ways turns out to be similar to it. Classical mechanics remains valid as a limiting case at speeds much lower than the speed of light and masses much less than those in the megaworld.
The theory of relativity showed the unity of space and time, expressed in a joint change in their characteristics depending on the concentration of masses and their movement. Time and space ceased to be considered independently of each other and the idea of a space-time four-dimensional continuum arose.
The theory of relativity also related mass and energy by the relation E=MC 2, where C is the speed of light. In the theory of relativity, “two laws - the law of conservation of mass and conservation of energy - lost their validity independent of each other and turned out to be combined into a single law, which can be called the law of conservation of energy or mass" (Heisenberg V. Physics and Philosophy. Part and Whole.- M., 1989.- P. 69). The phenomenon of annihilation, in which a particle and an antiparticle mutually destroy each other, and other phenomena of microworld physics confirm this conclusion.
So, the theory of relativity is based on the postulates of the constancy of the speed of light and the same laws of nature in all physical systems, and the main results to which it comes are as follows: the relativity of the properties of space-time; relativity of mass and energy; equivalence of heavy and inert masses (a consequence of what Galileo noted that all bodies, regardless of their composition and mass, fall in a gravitational field with the same acceleration).
Until the 20th century, the laws of the functioning of matter (Newton) and fields (Maxwell) were discovered. In the 20th century, attempts were made repeatedly to create a unified field theory that would combine material and field concepts, which, however, turned out to be unsuccessful.
In 1967, a hypothesis was put forward about the presence of tachyons, particles that move at speeds greater than the speed of light. If this hypothesis is ever confirmed, then it is possible that from the world of relativity, which is very uncomfortable for an ordinary person, in which only the speed of light is constant, we will return again to a more familiar world, in which absolute space resembles a reliable house with walls and a roof. But for now these are only dreams, the real feasibility of which can probably only be discussed in the 3rd millennium.
To conclude this section, we will quote words from Heisenberg’s book “Part and Whole” about what understanding as such means. “Understand” apparently means mastering ideas, concepts with the help of which we can consider a huge variety of different phenomena in their holistic connection, in other words, “embracing” them. Our thoughts calm down when we learn that any specific, seemingly confusing situation is only a particular consequence of something more general, thereby amenable to a simpler formulation. Reducing the motley variety of phenomena to a general and simple first principle, or, as the Greeks would say, “many” to “one,” is precisely what we call “understanding.” The ability to numerically predict an event is often a consequence of understanding, the possession of correct concepts, but it is not directly identical to understanding” (Heisenberg V. Physics and Philosophy. Part and Whole. - M., 1989. - P. 165).
