The first ideas of ancient scientists about what light is were very naive. There were several points of view. Some believed that special thin tentacles come out of the eyes and visual impressions arise when they feel objects. This point of view had a large number of followers, among whom were Euclid, Ptolemy and many other scientists and philosophers. Others, on the contrary, believed that the rays are emitted by a luminous body and, reaching the human eye, bear the imprint of a luminous object. This point of view was held by Lucretius, Democritus.

At the same time, Euclid formulated the law of rectilinear propagation of light. He wrote: "The rays emitted by the eyes propagate along a straight path."

However, later, already in the Middle Ages, such an idea of ​​the nature of light loses its meaning. Fewer and fewer scientists follow these views. And by the beginning of the XVII century. these points of view can be considered already forgotten.

In the 17th century, almost simultaneously, two completely different theories about what light is and what its nature is began to develop.

One of these theories is associated with the name of Newton, and the other with the name of Huygens.

Newton adhered to the so-called corpuscular theory of light, according to which light is a stream of particles coming from a source in all directions (transfer of matter).

According to Huygens' ideas, light is a stream of waves propagating in a special, hypothetical medium - ether, which fills all space and penetrates into all bodies.

Both theories have existed in parallel for a long time. None of them could win a decisive victory. Only the authority of Newton forced the majority of scientists to give preference to the corpuscular theory. The laws of light propagation known at that time from experience were more or less successfully explained by both theories.

On the basis of the corpuscular theory, it was difficult to explain why light beams, crossing in space, do not act on each other in any way. After all, light particles must collide and scatter.

The wave theory explained this easily. Waves, for example, on the surface of water, freely pass through each other without mutual influence.

However, the rectilinear propagation of light, leading to the formation of sharp shadows behind objects, is difficult to explain based on the wave theory. Under the corpuscular theory, the rectilinear propagation of light is simply a consequence of the law of inertia.

Such an indefinite position regarding the nature of light persisted until the beginning of the 19th century, when the phenomena of light diffraction (enveloping light around obstacles) and light interference (intensification or weakening of illumination when light beams were superimposed on each other) were discovered. These phenomena are inherent exclusively in wave motion. It is impossible to explain them with the help of corpuscular theory. Therefore, it seemed that the wave theory had won a final and complete victory.

Such confidence was especially strengthened when Maxwell showed in the second half of the 19th century that light is a special case of electromagnetic waves. Maxwell's work laid the foundations for the electromagnetic theory of light.

After the experimental discovery of electromagnetic waves by Hertz, there was no doubt that light behaves like a wave during propagation.

However, in the late 19th century, ideas about the nature of light began to change radically. It suddenly turned out that the rejected corpuscular theory is still relevant to reality.

When emitted and absorbed, light behaves like a stream of particles.

Discontinuous, or, as they say, quantum properties of light have been discovered. An unusual situation has arisen: the phenomena of interference and diffraction can still be explained by considering light as a wave, and the phenomena of radiation and absorption can be explained by considering light as a stream of particles. These two seemingly incompatible ideas about the nature of light in the 30s of the XX century managed to be consistently combined in a new outstanding physical theory - quantum electrodynamics.

1. Wave properties of light

Being engaged in the improvement of telescopes, Newton drew attention to the fact that the image given by the lens is colored at the edges. He became interested in this and was the first to "investigate the diversity of light rays and the peculiarities of colors resulting from this, which no one had even known before" (words from the inscription on Newton's grave). Newton's basic experiment was ingeniously simple. Newton guessed to send a light beam of small cross section to a prism. A beam of sunlight entered the darkened room through a small hole in the shutter. Falling on a glass prism, it refracted and gave on the opposite wall an elongated image with iridescent alternation of colors. Following the centuries-old tradition that the rainbow was considered to consist of seven primary colors, Newton also identified seven colors: purple, blue, cyan, green, yellow, orange and red. Newton called the rainbow strip itself a spectrum.

Closing the hole with red glass, Newton observed only a red spot on the wall, closing it with blue-blue, etc. It followed from this that it was not the prism that colored the white light, as previously assumed. The prism does not change the color, but only decomposes it into its component parts. White light has a complex structure. It is possible to distinguish beams of various colors from it, and only their joint action gives us the impression of a white color. In fact, if using a second prism rotated 180 degrees relative to the first. Collect all the beams of the spectrum, then again you get white light. If we single out any part of the spectrum, for example green, and force the light to pass through another prism, we will no longer get a further change in color.

Another important conclusion that Newton came to was formulated by him in his treatise on "Optics" as follows: "Light beams that differ in color differ in the degree of refraction." Violet rays are most strongly refracted, red ones are less than others. The dependence of the refractive index of light on its color is called dispersion (from the Latin word Dispergo, I scatter).

Newton further improved his observations of the spectrum in order to obtain purer colors. After all, the round colored spots of the light beam that passed through the prism partially overlapped each other. Instead of a round hole, a narrow slit (A) was used, illuminated by a bright source. Behind the slit was a lens (B) that produced an image on the screen (D) in the form of a narrow white stripe. If a prism (C) is placed in the path of the rays, then the image of the slit will be stretched into a spectrum, a colored strip, the color transitions in which from red to violet are similar to those observed in a rainbow. Newton's experience is shown in Fig. 1

If you cover the gap with colored glass, i.e. if you direct colored light at a prism instead of white light, the image of the slit will be reduced to a colored rectangle located at the corresponding place in the spectrum, i.e. depending on the color, the light will deviate to different angles from the original image. The described observation shows that rays of different colors are refracted differently by a prism.

Newton verified this important conclusion by many experiments. The most important of them consisted in determining the refractive index of rays of different colors extracted from the spectrum. For this purpose, a hole was cut in the screen on which the spectrum is obtained; by moving the screen, it was possible to release a narrow beam of rays of one color or another through the hole. This method of highlighting homogeneous rays is more perfect than highlighting with colored glass. Experiments have shown that such a selected beam, refracted in the second prism, no longer stretches the strip. Such a beam corresponds to a certain refractive index, the value of which depends on the color of the selected beam.

Thus, Newton's main experiments contained two important discoveries:

1. Light of different colors is characterized by different refractive indices in a given substance (dispersion).

2. White is a collection of simple colors.

Knowing that white light has a complex structure, one can explain the amazing variety of colors in nature. If an object, for example, a sheet of paper, reflects all the rays of various colors falling on it, then it will appear white. By covering the paper with a layer of paint, we do not create light of a new color, but retain some of the existing light on the sheet. Only red rays will now be reflected, the rest will be absorbed by a layer of paint. Grass and tree leaves appear green to us because of all the sun's rays falling on them, they reflect only green ones, absorbing the rest. If you look at the grass through red glass, which transmits only red rays, it will appear almost black.

We now know that different colors correspond to different wavelengths of light. Therefore, Newton's first discovery can be formulated as follows: the refractive index of matter depends on the wavelength of light. It usually increases as the wavelength decreases.

The interference of light was observed for a very long time, but they just did not realize it. Many have seen the interference pattern when they had fun blowing soap bubbles in childhood or watched the iridescent overflow of colors of a thin film of kerosene on the surface of the water. It is the interference of light that makes the soap bubble so admirable.

The characteristic of the state of electrons in an atom is based on the position of quantum mechanics about the dual nature of an electron, which simultaneously has the properties of a particle and a wave.

For the first time, the dual corpuscular-wave nature was established for light. Studies of a number of phenomena (radiation from incandescent bodies, the photoelectric effect, atomic spectra) led to the conclusion that energy is emitted and absorbed not continuously, but discretely, in separate portions (quanta). The assumption of energy quantization was first made by Max Planck (1900) and substantiated by Albert Einstein (1905): the quantum energy (∆E) depends on the radiation frequency (ν):

∆Е = hν, where h = 6.63 10 -34 J s is Planck's constant.

Equating the energy of a photon hν to the total reserve of its energy mс 2 and, taking into account that ν=с/λ, we obtain a relation expressing the relationship between the wave and corpuscular properties of a photon:

In 1924 Louis de Broglie suggested that the dual corpuscular-wave nature is inherent not only in radiation, but also in any material particle: each particle having a mass (m) and moving at a speed (υ) corresponds to a wave process with a wavelength λ:

λ = h / mυ(55)

The smaller the particle mass, the longer the wavelength. Therefore, it is difficult to detect the wave properties of macroparticles.

In 1927, the American scientists Davisson and Germer, the Englishman Thomson and the Soviet scientist Tartakovskii independently discovered electron diffraction, which was an experimental confirmation of the wave properties of electrons. Later, diffraction (interference) of α-particles, neutrons, protons, atoms and even molecules was discovered. Currently, electron diffraction is used to study the structure of matter.

The wave properties of elementary particles contain one of the principles of wave mechanics: uncertainty principle (W. Heisenberg 1925): for small bodies on an atomic scale, it is impossible to simultaneously accurately determine the position of a particle in space and its velocity (momentum). The more precisely the coordinates of a particle are determined, the less certain its velocity becomes, and vice versa. The uncertainty relation has the form:

where ∆x is the uncertainty of the particle position, ∆Р x is the uncertainty of the magnitude of the momentum or velocity in the x direction. Similar relationships are also written for the y and z coordinates. The value ℏ included in the uncertainty relation is very small, therefore, for macroparticles, the uncertainties in the values ​​of coordinates and momenta are negligible.

Therefore, it is impossible to calculate the trajectory of the electron in the field of the nucleus; one can only estimate the probability of its being in the atom using wave function ψ, which replaces the classical notion of a trajectory. The wave function ψ characterizes the wave amplitude depending on the electron coordinates, and its square ψ 2 determines the spatial distribution of the electron in the atom. In the simplest version, the wave function depends on three spatial coordinates and makes it possible to determine the probability of finding an electron in atomic space or its orbital . In this way, atomic orbital (AO) is a region of atomic space in which the probability of finding an electron is greatest.

Wave functions are obtained by solving the fundamental relation of wave mechanics - equationsSchrödinger (1926) :

(57)

where h is Planck's constant, is a variable, U is the potential energy of the particle, E is the total energy of the particle, x, y, z, are the coordinates.

Thus, the quantization of the energy of a microsystem follows directly from the solution of the wave equation. The wave function completely characterizes the state of the electron.

The wave function of a system is a function of the state of the system, the square of which is equal to the probability density of finding electrons at each point in space. It must satisfy standard conditions: be continuous, finite, single-valued, vanish where there is no electron.

An exact solution is obtained for a hydrogen atom or hydrogen-like ions; for many-electron systems, various approximations are used. The surface that limits 90-95% of the probability of finding an electron or electron density is called the boundary. The atomic orbital and the electron cloud density have the same boundary surface (shape) and the same spatial orientation. The atomic orbitals of an electron, their energy and direction in space depend on four parameters - quantum numbers : main, orbital, magnetic and spin. The first three characterize the motion of an electron in space, and the fourth - around its own axis.

Quantum numbern – main . It determines the energy level of an electron in an atom, the distance of the level from the nucleus, and the size of the electron cloud. It takes integer values ​​from 1 to ∞ and corresponds to the period number. From the periodic system for any element, by the number of the period, you can determine the number of energy levels of the atom, and which energy level is external. The more n, the greater the energy of interaction of the electron with the nucleus. At n= 1 hydrogen atom is in the ground state, at n> 1 - in excited. If a n∞, then the electron has left the atomic volume. The atom is ionized.

For example, the element cadmium Cd is located in the fifth period, so n=5. In its atom, electrons are distributed over five energy levels (n = 1, n = 2, n = 3, n = 4, n = 5); the fifth level will be external (n = 5).

Since the electron, along with the properties of a wave, has the properties of a material particle, it, having a mass m, a speed of movement V, and being at a distance from the nucleus r, has a moment of momentum: μ=mVr.

The angular momentum is the second (after energy) characteristic of an electron and is expressed in terms of a side (azimuthal, orbital) quantum number.

Orbital quantum numberl- determines the shape of the electron cloud (Fig. 7), the energy of the electron at the sublevel, the number of energy sublevels. Takes values ​​from 0 to n– 1. Other than numerical values l has letters. Electrons with the same value l form a sublevel.

In each quantum level, the number of sublevels is strictly limited and equal to the number of the layer. Sublevels, like energy levels, are numbered in the order of their distance from the nucleus (Table 26).

According to the concepts of classical physics, light is electromagnetic waves in a certain frequency range. However, the interaction of light with matter occurs as if light were a stream of particles.

In Newton's time, there were two hypotheses about the nature of light - corpuscular, which Newton adhered to, and wave. Further development of experimental technique and theory made a choice in favor of wave theory .

But at the beginning of the XX century. new problems arose: the interaction of light with matter could not be explained within the framework of wave theory.

When a piece of metal is illuminated with light, electrons fly out of it ( photoelectric effect). It was to be expected that the speed of the emitted electrons (their kinetic energy) would be the greater, the greater the energy of the incident wave (the intensity of light), but it turned out that the speed of electrons generally does not depend on the intensity of light, but is determined by its frequency (color) .

Photography is based on the fact that some materials darken after illumination with light and subsequent chemical treatment, and the degree of their blackening is proportional to the illumination and exposure time. If a layer of such material (photographic plate) is illuminated with light at a certain frequency, then after development, the homogeneous surface will turn black. With a decrease in light intensity, we will get homogeneous surfaces with less and less blackening (different shades of gray). And it all ends with the fact that at very low illumination we get not a very small degree of blackening of the surface, but black dots randomly scattered over the surface! As if the light hit only these places.

Features of the interaction of light with matter forced physicists to return to corpuscular theory.

The interaction of light with matter occurs as if light were a stream of particles, energy and pulse which are related to the frequency of light by the relations

E=hv;p=E /c=hv /c,

where h is Planck's constant. These particles are called photons.

photoelectric effect could be understood if one took the point of view corpuscular theory and consider light as a stream of particles. But then the problem arises, what to do with other properties of light, which were dealt with by a vast branch of physics - optics based on the fact that light is an electromagnetic wave.

The situation in which individual phenomena are explained using special assumptions that are inconsistent with each other or even contradict one another is considered unacceptable, since physics claims to create a unified picture of the world. And the confirmation of the validity of this claim was just the fact that shortly before the difficulties that arose in connection with the photoelectric effect, optics was reduced to electrodynamics. Phenomena interference and diffraction definitely did not agree with ideas about particles, but some properties of light are equally well explained from both points of view. An electromagnetic wave has energy and momentum, and the momentum is proportional to the energy. When light is absorbed, it transfers its momentum, i.e., a pressure force proportional to the light intensity acts on the barrier. The flow of particles also exerts pressure on the barrier, and with a suitable relationship between the energy and momentum of the particle, the pressure will be proportional to the intensity of the flow. An important achievement of the theory was the explanation of the scattering of light in the air, as a result of which it became clear, in particular, why the sky is blue. It followed from the theory that the frequency of light does not change during scattering.

However, if you take the point of view corpuscular theory and consider that the characteristic of light, which in the wave theory is associated with frequency (color), in the corpuscular theory is associated with the energy of the particle, it turns out that during scattering (collision of a photon with a scattering particle), the energy of the scattered photon should decrease . Specially carried out experiments on the scattering of X-rays, which correspond to particles with an energy three orders of magnitude higher than for visible light, showed that corpuscular theory true. Light should be considered a stream of particles, and the phenomena of interference and diffraction were explained within the framework of quantum theory. But at the same time, the very concept of a particle as an object of vanishingly small size, moving along a certain trajectory and having a certain speed at each point, has also changed.

The new theory does not cancel the correct results of the old one, but it can change their interpretation. So, if in wave theory Color is associated with wavelength corpuscular it is related to the energy of the corresponding particle: the photons that cause the sensation of red in our eye have less energy than those of blue. material from the site

For light, an experiment was carried out with electrons (Yung-ha's experience). The illumination of the screen behind the slits had the same form as for electrons, and this picture light interference, falling on the screen from two slits, served as proof of the wave nature of light.

Problem related to wave and corpuscular properties of particles has a really long history. Newton believed that light is a stream of particles. But at the same time, the hypothesis about the wave nature of light, associated, in particular, with the name of Huygens, was in circulation. The data on the behavior of light that existed at that time (rectilinear propagation, reflection, refraction and dispersion) were equally well explained from both points of view. In this case, of course, nothing definite could be said about the nature of light waves or particles.

Later, however, after the discovery of phenomena interference and diffraction light (beginning of the 19th century), the Newtonian hypothesis was abandoned. The "wave or particle" dilemma for light was experimentally resolved in favor of a wave, although the nature of light waves remained unclear. Further, their nature became clear. Light waves turned out to be electromagnetic waves of certain frequencies, i.e., the propagation of disturbances in the electromagnetic field. The wave theory seemed to have finally triumphed.

On this page, material on the topics:

Wave properties. A contemporary of Isaac Newton, the Dutch physicist Christian Huygens, did not reject the existence of corpuscles, but believed that they are not emitted by luminous bodies, but fill all space. Huygens represented the process of light propagation not as a progressive movement, but as a successive process of transferring the impact of one corpuscle to another.

Supporters of Huygens expressed the opinion that light is a propagating oscillation in a special medium - "ether", which fills the entire world space and which freely penetrates into all bodies. Light excitation from a light source is transmitted by ether in all directions.

Thus, the first wave ideas about the nature of light arose. The main value of the initial wave theory of light is the principle originally formulated by Huygens and then developed by Fresnel. The Huygens-Fresnel principle states that each kidney, which is reached by light excitation, in turn becomes the center of secondary waves and transmits them in all directions to neighboring kidneys.

The wave properties of light are most clearly manifested in the phenomena of interference and diffraction.

The interference of light lies in the fact that when two waves are mutually located, the oscillations can be strengthened or weakened. The principle of interference was discovered in 1801 by the Englishman Thomas Young (1773-1829), a physician by profession. Jung performed the now classic experiment with two holes. On the screen, two closely spaced holes were pierced with the tip of a pin, which were illuminated by sunlight from a small hole in the curtained window. Behind the screen, instead of two bright spots, a series of alternating dark and light rings was observed.

A necessary condition for observing the interference pattern is the coherence of the waves (a coordinated flow of oscillatory or wave processes).

The phenomenon of interference is widely used in devices - interferometers, with the help of which various precise measurements are carried out and the surface finish of parts is controlled, as well as many other control operations.

In 1818, Fresnel submitted an extensive report on the diffraction of light to the competition of the Paris Academy of Sciences. Considering this report, A. Poisson (1781-1840) came to the conclusion that according to the theory proposed by Fresnel, under certain conditions, in the center of the diffraction pattern from an opaque round obstacle in the path of light there should be a bright spot, not a shadow. It was a stunning conclusion. D.F.Arago (1786-1853) immediately set up an experiment, and Poisson's calculations were confirmed. Thus, the conclusion made by Poisson, outwardly contradicting Fresnel's theory, turned, with the help of Arago's experiment, into one of the proofs of its validity, and also marked the beginning of the recognition of the wave nature of light.

The phenomenon of light deflection from the rectilinear direction of propagation is called diffraction.

Many optical devices are based on the phenomenon of diffraction. In particular, crystallographic equipment uses X-ray diffraction.

The wave nature of light and the transverse nature of light waves are also proved by the phenomenon polarization. The essence of polarization is clearly demonstrated by a simple experiment: when light passes through two transparent crystals, its intensity depends on the mutual orientation of the crystals. With the same orientation, light passes without attenuation. When one of the crystals is rotated by 90°, the light is completely extinguished, i.e. does not pass through crystals.

The wave nature of light is also confirmed by the phenomenon of light dispersion. A narrow parallel beam of white light, when passing through a glass prism, decomposes into beams of light of different colors. The color band is called the continuous spectrum. The dependence of the speed of propagation of light in a medium on the wavelength is called the dispersion of light. Dispersion was discovered by I. Newton.

The decomposition of white light is explained by the fact that it consists of electromagnetic waves with different wavelengths and the refractive index depends on the wavelength. The highest value of the refractive index for light with the shortest wavelength is violet, the lowest for the longest wavelength light is red. Experiments have shown that in a vacuum the speed of light is the same for light of any wavelength.

The study of the phenomena of diffraction, interference, polarization and dispersion of light led to the establishment of the wave theory of light.

Quantum properties of light. In 1887, G. Hertz, when illuminating a zinc plate connected to the rod of an electrometer, discovered the phenomenon of the photoelectric effect. If a positive charge is transferred to the plate and rod, then the electrometer does not discharge when the plate is illuminated. When a negative electric charge is imparted to the plate, the electrometer is discharged as soon as radiation hits the plate. This experiment proves that negative centric charges escape from the surface of a metal plate under the action of light. Measurements of the charge and mass of the particles ejected by the light showed that these particles are electrons. The phenomenon of the emission of electrons by a substance under the action of electromagnetic radiation is called the photoelectric effect.

The quantitative regularities of the photoelectric effect were established in 1888-1889. Russian physicist A.G. Stoletov (1839-1896).

It was not possible to explain the basic laws of the photoelectric effect on the basis of the electromagnetic theory of light. The electromagnetic theory of light could not explain the independence of the energy of photoelectrons from the intensity of light radiation, the existence of the red border of the photoelectric effect, the proportionality of the kinetic energy of photoelectrons to the frequency of light.

The electromagnetic theory of Maxwell and the electronic theory of Lorentz, despite their enormous successes, were somewhat contradictory and a number of difficulties were encountered in their application. Both theories were based on the ether hypothesis, only the "elastic ether" was replaced by "electromagnetic ether" (Maxwell's theory) or "fixed ether" (Lorentz's theory). Maxwell's theory could not explain the processes of emission and absorption of light, the photoelectric effect, Compton scattering, etc. Lorentz's theory, in turn, could not explain many phenomena associated with the interaction of light with matter, in particular the question of the distribution of energy over wavelengths during thermal blackbody radiation.

These difficulties and contradictions were overcome thanks to the bold hypothesis put forward in 1900 by the German physicist M. Planck, according to which light emission does not occur continuously, but discretely, i.e., in certain portions (quanta), the energy of which is determined by the frequency n:

where h is Planck's constant.

Planck's theory does not need the concept of aether. She explained the thermal radiation of a completely black body.

A. Einstein in 1905 created quantum theory of light: not only the emission of light, but also its propagation occurs in the form flux of light quanta - photons, the energy of which is determined by the above Planck formula, and the momentum

where l is the wavelength.

The quantum properties of electromagnetic waves are most fully manifested in Compton effect: When monochromatic X-ray radiation is scattered by a substance with light atoms, along with the radiation characterized by the initial wavelength, radiation with a longer wavelength is observed in the composition of the scattered radiation.

Quantum ideas about light are in good agreement with the laws of radiation and absorption of light, the laws of interaction, radiation with matter. Such well-studied phenomena as interference, diffraction and polarization of light are well explained in terms of wave concepts. All the variety of studied properties and laws of light propagation, its interaction with matter shows that light has a complex nature: it is a unity of opposite properties - corpuscular (quantum) and wave (electromagnetic). The long path of development has led to modern ideas about the dual corpuscular-wave nature of light. The above expressions connect the corpuscular characteristics of radiation - the mass and energy of a quantum - with the wave characteristics - the frequency of oscillations and the wavelength. In this way, light is a unity of discreteness and continuity.

Questions for self-examination

Question 1. What is the most important task of natural science.

1. cognitive

2. worldview

3. teleological

4. creation of a natural-science picture of the world

Question 2. Name the most general, important fundamental concepts of the physical description of nature.

1. matter

2. movement

3. space

Question 3. What is the philosophical category to denote the objective reality, which is displayed by our sensations, existing independently of them.

1. consciousness

2. display

3. matter

Wave and corpuscular properties of light - page №1/1

WAVE AND CORPUSCULAR PROPERTIES OF LIGHT

© Moiseev B.M., 2004

Kostroma State University
1 Maya Street, 14, Kostroma, 156001, Russia
Email: [email protected] ; [email protected]

The possibility of considering light as a periodic sequence of excitations of the physical vacuum is logically deduced. As a consequence of this approach, the physical nature of the wave and corpuscular properties of light is explained.

A logical conclusion of the possibility to regard light as a period sequence of physical vacuum excitements is given in the article. As a consequence of such an approach the physical nature of wave and corpuscular characteristics of light are explained here.

Introduction

Centuries-old attempts to understand the physical nature of light phenomena were interrupted at the beginning of the 20th century by the introduction of the dual properties of matter into the axiomatics of the theory. Light began to be considered both a wave and a particle at the same time. However, the radiation quantum model was built formally, and there is still no unambiguous understanding of the physical nature of the radiation quantum.

This work is devoted to the formation of new theoretical ideas about the physical nature of light, which should explain qualitatively the wave and corpuscular properties of light. Earlier, the main provisions of the developed model and the results obtained within the framework of this model were published:

1. A photon is a set of elementary excitations of vacuum propagating in space in the form of a chain of excitations with a constant relative to vacuum speed, independent of the speed of the light source. For an observer, the photon's speed depends on the observer's speed relative to vacuum, modeled logically as absolute space.

2. Elementary vacuum excitation is a pair of photons, a dipole formed by two (+) and (-) charged particles. The dipoles rotate and have an angular momentum, collectively making up the photon's spin. The radius of rotation of photons and the angular velocity are related by the dependence Rω = const .

3. Photons can be thought of as thin long cylindrical needles. Imaginary surfaces of cylinders-needles are formed by spiral trajectories of photons. The higher the rotation frequency, the thinner the photon needle. One complete revolution of a pair of photons determines the wavelength in space along the direction of motion.

4. The energy of a photon is determined by the number of pairs of photons n in one photon: ε = nh E, where h E is a value equal to Planck's constant in units of energy .

5. The quantitative value of the photon spin ћ is obtained. An analysis of the relationship between the energy and kinematic parameters of a photon has been carried out. As an example, the kinematic parameters of a photon produced by the 3d2p transition in a hydrogen atom are calculated. The length of a photon in the visible part of the spectrum is meters.

6. The mass of a pair of photons was calculated m 0 = 1.474 10 -53 g, which coincides in order of magnitude with the upper estimate of the photon mass m 

7. A conclusion was made about the change in the constants C and h when a photon moves in a gravitational field.

From the periodic structure of a photon, the reason for the wave properties of light is intuitively clear: the mathematics of a wave, as a process of mechanical oscillation of a physical medium, and the mathematics of a periodic process of any qualitative nature, coincide. The papers give a qualitative explanation of the wave and corpuscular properties of light. This article continues the development of ideas about the physical nature of light.

Wave properties of light

As noted earlier, the elements of periodicity associated with the physical nature of light cause the manifestation of wave properties. The manifestation of the wave properties of light has been established by numerous observations and experiments, and therefore cannot be in doubt. A mathematical wave theory of the Doppler effect, interference, diffraction, polarization, dispersion, absorption and scattering of light has been developed. The wave theory of light is organically connected with geometric optics: in the limit, as  → 0, the laws of optics can be formulated in the language of geometry.

Our model does not cancel the mathematical apparatus of the wave model. The main goal and the main result of our work is the introduction of such changes in the axiomatics of the theory that deepen the understanding of the physical essence of the phenomenon and eliminate paradoxes.

The main paradox of modern concepts of light is wave-particle duality (CWD). In accordance with the laws of formal logic, light cannot be both a wave and a particle in the traditional sense of these terms. The concept of a wave implies a continuum, a homogeneous medium in which periodic perturbations of the elements of the continuum arise. The concept of a particle implies the isolation and autonomy of individual elements. The physical interpretation of HPC is not so simple.

The combination of corpuscular and wave models according to the principle “a wave is a perturbation of a set of particles” raises an objection, because the presence of wave properties in a single, single particle of light is considered to be firmly established. The interference of rarely flying photons was discovered by Janoshi, but there are no quantitative results, details and detailed analysis of the experiment in the training course. Information about such important, fundamental results is not available either in reference books or in the course on the history of physics. Apparently, the question of the physical nature of light is already a deep rear of science.

Let us try to reconstruct the quantitative parameters of Yanoshi's experiment, which are logically essential for interpreting the results, based on a sparing description of similar experiments by Biberman, Sushkin, and Fabrikant with electrons. Obviously, in Yanoshi's experiment, the interference pattern obtained from a short light pulse of high intensity J B was compared with the pattern obtained over a long time from a weak photon flux J M. The essential difference between the two situations under consideration is that in the case of a flux J M, the interaction of photons within diffractive instrument should be excluded.

Since Janoshi did not find any difference in the interference patterns, let's see what conditions are necessary for this within the framework of our model.

A photon of length L f = 4.5 m passes a given point in space in time τ = L f / C = 4.5 /3ּ10 8 ≈ 1.5ּ10 –8 s. If the diffraction system (device) has a size of about 1 m, then the time it takes for a photon to pass through the device of length L f will be longer: τ’ = (L f + 1) / C ≈ 1.8ּ10 –8 s.

An outside observer cannot see single photons. An attempt to fix a photon destroys it - there is no other option to “see” an electrically neutral particle of light. The experiment uses time-averaged properties of light, in particular, intensity (energy per unit time). So that photons do not intersect within the diffraction device, it is necessary to separate them in space along the trajectory of movement so that the time of passage of the device τ' is less than the time t dividing the arrival of successive photons to the installation, i.e. τ' 1.8ּ10 –8 s.

In experiments with electrons, the average time interval between two particles successively passing through the diffraction system was approximately 3-10 4 times longer than the time spent by one electron to pass through the entire device. For point particles, this relation is convincing.

The experiment with light has a significant difference from the experiment with electrons. If the uniqueness of electrons can be controlled due to a slight distortion of their energy, then this is impossible with photons. In the experiment with photons, the belief in the isolation of photons in space cannot be complete; it is statistically possible for two photons to arrive almost simultaneously. This can give a weak interference pattern over a long observation time.

The results of Yanoshi's experiments are indisputable, however, such a conclusion cannot be made about the theory of experience. In theory, it is actually postulated that the interference pattern arises solely as a result of the interaction of particles with each other on the surface of the screen. In the case of strong light fluxes and the presence of many particles, this is intuitively the most probable cause of interference, but for weak light fluxes, another reason for the appearance of periodicity in screen illumination may also become significant. Light changes direction when it interacts with a solid body. Slit edges, diffraction grating strokes and other obstacles that cause diffraction - this is a surface that is far from ideal, not only in terms of surface finish. Atoms of the surface layer are a periodic structure with a period comparable to the size of an atom, i.e., the periodicity is of the angstrom order. The distance between photon pairs inside a photon is L 0 ≈ 10 –12 cm, which is 4 orders of magnitude smaller. The reflection of photo pairs from the periodic structure of the surface should cause a repetition of illuminated and unilluminated places on the screen.

Inequality in the directions of propagation of the reflected light should always be, when reflected from any surface, but with strong light fluxes, only average characteristics are significant, and this effect does not appear. For weak light fluxes, this can lead to screen illumination that resembles interference.

Since the dimensions of an electron are also much smaller than the dimensions of the periodic structure of the surface of the body, for electrons there should also be an inequality in the directions of diffracting particles, and for weak electron fluxes this may be the only reason for the manifestation of wave properties.

Thus, the presence of wave properties in particles, whether photons or electrons, can be explained by the presence of wave properties of the reflective or refractive surface of a diffractive instrument.

For a possible experimental confirmation (or refutation) of this hypothesis, some effects can be predicted.

Effect 1

For strong light fluxes, the main reason for the interference properties of light is the periodic structure of the light itself, an extended photon. Pairs of photons from different photons either reinforce each other on the screen when the phase coincides (vectors r between the centers of the photons of the interacting pairs coincide in direction), or weaken in the case of a phase mismatch (vectors r between the centers of the photos do not coincide in direction). In the latter case, pairs of photos from different photons do not cause a joint simultaneous action, but they fall into those parts of the screen where a decrease in illumination is observed.

If the screen is a transparent plate, then the following effect can be observed: a minimum in reflected light corresponds to a maximum in transmitted light. In places where a minimum of illumination is observed in reflected light, light also enters, but it is not reflected in these places, but passes inside the plate.

The mutual complementarity of the light reflected and transmitted through the plate in the phenomenon of interference is a well-known fact, described in theory by a well-developed formal mathematical apparatus of the wave model of light. In particular, the theory introduces a loss of a half-wave during reflection, and this “explains” the phase difference between the transmitted and reflected components.

What is new in our model is the explanation of the physical nature of this phenomenon. We argue that for weak light fluxes, when the interaction of photons within the diffraction device is excluded, the essential reason for the formation of an interference pattern will not be the periodic structure of the light itself, but the periodic structure of the surface of the device that causes diffraction. In this case, there will no longer be interaction of pairs of photons from different photons on the surface of the screen, and interference should manifest itself in the fact that in those places where the light hits, there will be a maximum of illumination, in other places it will not be. In places with a minimum of illumination, the light will not get at all, and this can be checked the absence of mutual complementarity of the interference pattern for reflected and transmitted light.

Effect 2

Another possibility of testing the prediction under consideration and our hypothesis as a whole is that for weak light fluxes, a diffraction device made of another material, which differs by a different surface density of atoms, should give a different interference pattern for the same light output. This prediction is also verifiable in principle.

Effect 3

The atoms of the surface of the reflecting body participate in thermal motion, the nodes of the crystal lattice perform harmonic vibrations. An increase in the crystal temperature should lead to blurring of the interference pattern in the case of weak light fluxes, since in this case the interference depends only on the periodic structure of the reflecting surface. For strong light fluxes, the effect of the temperature of the diffraction device on the interference pattern should be weaker, although it is not excluded, since thermal vibrations of the crystal lattice sites should violate the coherence condition for the reflected pairs of photons from different photons. This prediction is also verifiable in principle.

Corpuscular properties of light

In our publications, we have proposed the term “structural model of a photon”. Analyzing today a combination of words enclosed in quotation marks, it is necessary to recognize it as extremely unsuccessful. The point is that in our model the photon as a localized particle does not exist. A quantum of radiant energy, identified in modern theory with a photon, in our model is a set of vacuum excitations, called pairs of photons. Excitations are distributed in space along the direction of motion. Despite the enormous extent for the scale of the microworld, due to the smallness of the time interval during which such a set of pairs flies past any microobject or collides with it, and also due to the relative inertia of the objects of the microworld, quanta can be completely absorbed by these microobjects. A quantum photon is perceived as a separate particle only in the process of such interaction with micro-objects, when the effect from the interaction of a micro-object with each pair of photons can be accumulated, for example, in the form of excitation of the electron shell of an atom or molecule. Light exhibits corpuscular properties in the course of such an interaction, when an essential, model-conscious, theoretically taken into account factor is the emission or absorption of a certain discrete amount of light energy.

Even a formal idea of ​​energy quanta allowed Planck to explain the features of black body radiation, and Einstein to understand the essence of the photoelectric effect. The concept of discrete portions of energy helped to describe in a new way such physical phenomena as light pressure, light reflection, dispersion - what has already been described in the language of the wave model. The idea of ​​energy discreteness, and not the idea of ​​point particles-photons - that's what is really essential in the modern corpuscular model of light. The discreteness of the energy quantum makes it possible to explain the spectra of atoms and molecules, but the localization of the energy of the quantum in one isolated particle conflicts with the experimental fact that the time of emission and the time of absorption of the energy quantum by an atom is quite large on the scale of the microworld - about 10–8 s. If a quantum is a localized point particle, then what happens to this particle in a time of 10–8 s? The introduction of an extended quantum-photon into the physical model of light makes it possible to qualitatively understand not only the processes of emission and absorption, but also the corpuscular properties of radiation in general.

Quantitative parameters of photos

In our model, the main object of consideration is a couple of photos. Compared to the dimensions of a photon (longitudinal dimensions for visible light are meters), the excitation of vacuum in the form of a pair of photons can be considered pointlike (the longitudinal dimension is about 10–14 m) . Let us quantify some photo parameters. It is known that γ-quanta are produced during the annihilation of an electron and a positron. Let two γ-quanta be born. Let us estimate the upper limit of their quantitative parameters, assuming the energy of the electron and positron to be equal to the rest energy of these particles:

. (1)

The number of photo pairs that appear is:

. (2)

The total charge of all (–) photons is –e, where e is the electron charge. The total charge of all (+) photons is +e. Let us calculate the modulus of the charge carried by one photo:

Cl. (3)

Approximately, not taking into account the dynamic interaction of moving charges, we can assume that the centripetal force of a rotating pair of photons is the force of their electrostatic interaction. Since the linear speed of rotating charges is equal to C, we get (in the SI system):

, (4)

where m 0 / 2 \u003d h E / C 2 - the mass of one photo. From (4) we obtain an expression for the radius of rotation of photon charge centers:

m. (5)

Considering the “electrical” cross section of a photon as the area of ​​a circle S of radius R El, we obtain:

The paper provides a formula for calculating the cross section of a photon in the framework of QED:

, (7)

where σ is measured in cm 2. Assuming ω = 2πν, and ν = n (without taking into account the dimension), we obtain an estimate of the cross section using the QED method:

. (8)

The difference with our estimate of the photon cross section is 6 orders of magnitude, or about 9%. At the same time, it should be noted that our result for the photon cross section ~10 –65 cm 2 was obtained as an upper estimate for the annihilation of immobile particles, while the real electron and positron have the energy of motion. Taking into account the kinetic energy, the cross section should be smaller, since in formula (1) the energy of particles passing into radiation will be greater, and, consequently, the number of pairs of photons will be greater. The calculated value of the charge of one photo will be less (formula 3), therefore, R El (formula 5) and the cross section S (formula 6) will be less. With this in mind, our estimate of the photon cross section should be recognized as approximately coinciding with the QED estimate.

Note that the specific charge of phot coincides with the specific charge of an electron (positron):

. (9)

If a phot (like an electron) has a hypothetical “core”, in which its charge is concentrated, and a “fur coat” from a perturbed physical vacuum, then the “electrical” cross section of a pair of photons should not coincide with the “mechanical” cross section. Let the centers of mass of photons rotate around a circle of radius R Mex with a speed C. Since C = ωR Mex, we obtain:

. (10)

Thus, the length of the circle along which the photo centers of mass rotate is equal to the wavelength, which is quite natural when the translational and rotational velocities are equal in our interpretation of the concept of “wavelength”. But in this case, it turns out that for photons obtained as a result of the annihilation considered above, R Mex ≈ 3.8∙10 –13 m ≈ 10 22 ∙R El. The fur coat of the perturbed vacuum, surrounding the cores of the photons, has gigantic dimensions in comparison with the core itself.

Of course, these are all rather rough estimates. Any new model cannot compete in accuracy with an already existing model that has reached its dawn. For example, when the heliocentric model of Copernicus appeared, for about 70 years practical astronomical calculations were carried out in accordance with the geocentric model of Ptolemy, since this led to a more accurate result.

The introduction of models on a fundamentally new basis into science is not only a collision with subjective opposition, but also an objective loss of the accuracy of calculations and predictions. Paradoxical results are also possible. The resulting ratio of orders of ~10 22 between the electrical and mechanical radii of rotation of photons is not only unexpected, but also physically incomprehensible. The only way to somehow understand the ratio obtained is to assume that the rotation of a pair of photons has a vortex character, since in this case, if the linear velocities of components at different distances from the center of rotation are equal, their angular velocities should be different.

Intuitively, the vortex nature of the rotation of a three-dimensional structure from a thin medium - physical vacuum, is even more understandable than the idea of ​​the rotation of a pair of photons, reminiscent of the rotation of a solid body. An analysis of the vortex motion should further lead to a new qualitative understanding of the process under consideration.

Results and conclusions

The work continues the development of ideas about the physical nature of light. The physical nature of corpuscular-wave dualism is analyzed. Fundamentally verifiable effects are predicted in experiments on the interference and diffraction of weak light fluxes. Quantitative calculations of mechanical and electrical parameters of photons have been performed. The cross section of a pair of photons is calculated and a conclusion is made about the vortex structure of the pair.

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