I think it's safe to say that no one understands quantum mechanics.
Physicist Richard Feynman
It is no exaggeration to say that the invention of semiconductor devices was a revolution. Not only is this an impressive technological achievement, but it also paved the way for events that will change modern society forever. Semiconductor devices are used in all kinds of microelectronic devices, including computers, certain types of medical diagnostic and treatment equipment, and popular telecommunications devices.
But behind this technological revolution is even more, a revolution in general science: the field quantum theory. Without this leap in understanding the natural world, the development of semiconductor devices (and more advanced electronic devices under development) would never have succeeded. Quantum physics is an incredibly complex branch of science. This chapter only provides a brief overview. When scientists like Feynman say "nobody understands [it]", you can be sure that this is a really difficult topic. Without a basic understanding of quantum physics, or at least an understanding of the scientific discoveries that led to their development, it is impossible to understand how and why semiconductor electronic devices work. Most electronics textbooks try to explain semiconductors in terms of "classical physics", making them even more confusing to understand as a result.
Many of us have seen atomic model diagrams that look like the picture below.
Rutherford atom: negative electrons revolve around a small positive nucleus
Tiny particles of matter called protons And neutrons, make up the center of the atom; electrons revolve like planets around a star. The nucleus carries a positive electrical charge due to the presence of protons (neutrons have no electrical charge), while the counterbalancing negative charge of an atom resides in the orbiting electrons. Negative electrons are attracted to positive protons like planets are attracted to the Sun, but the orbits are stable due to the movement of electrons. We owe this popular model of the atom to the work of Ernest Rutherford, who experimentally determined around 1911 that the positive charges of atoms are concentrated in a tiny, dense nucleus, and not evenly distributed along the diameter, as explorer J. J. Thomson had previously assumed.
Rutherford's scattering experiment consists of bombarding a thin gold foil with positively charged alpha particles, as shown in the figure below. Young graduate students H. Geiger and E. Marsden got unexpected results. The trajectory of some alpha particles was deviated by a large angle. Some alpha particles were scattered backwards, at an angle of almost 180°. Most of the particles passed through the gold foil without changing their trajectory, as if there was no foil at all. The fact that several alpha particles experienced large deviations in their trajectory indicates the presence of nuclei with a small positive charge.
Rutherford scattering: a beam of alpha particles is scattered by thin gold foil Although Rutherford's model of the atom was supported by experimental data better than Thomson's, it was still imperfect. Further attempts were made to determine the structure of the atom, and these efforts helped pave the way for the strange discoveries of quantum physics. Today our understanding of the atom is a bit more complex. Yet despite the revolution of quantum physics and its contribution to our understanding of the structure of the atom, Rutherford's depiction of the solar system as the structure of an atom has taken root in popular consciousness to the extent that it persists in the fields of education, even if it is misplaced.
Consider this brief description of the electrons in an atom, taken from a popular electronics textbook:
The spinning negative electrons are attracted to the positive nucleus, which leads us to the question of why the electrons don't fly into the nucleus of the atom. The answer is that the rotating electrons remain in their stable orbit due to two equal but opposite forces. The centrifugal force acting on the electrons is directed outward, and the attractive force of the charges is trying to pull the electrons towards the nucleus.
In accordance with Rutherford's model, the author considers electrons to be solid pieces of matter occupying round orbits, their inward attraction to the oppositely charged nucleus is balanced by their movement. The use of the term "centrifugal force" is technically incorrect (even for orbiting planets), but this is easily forgiven due to the popular acceptance of the model: in fact, there is no such thing as force, repulsiveany rotating body from the center of its orbit. This seems to be so because the body's inertia tends to keep it moving in a straight line, and since the orbit is a constant deviation (acceleration) from rectilinear motion, there is a constant inertial reaction to any force that attracts the body to the center of the orbit (centripetal), whether either gravity, electrostatic attraction, or even the tension of a mechanical bond.
However, the real problem with this explanation in the first place is the idea of electrons moving in circular orbits. A proven fact that accelerated electric charges emit electromagnetic radiation, this fact was known even in Rutherford's time. Since rotational motion is a form of acceleration (a rotating object in constant acceleration, pulling the object away from its normal rectilinear motion), electrons in a rotating state must emit radiation like mud from a spinning wheel. Electrons accelerated along circular paths in particle accelerators called synchrotrons are known to do this, and the result is called synchrotron radiation. If electrons were to lose energy in this way, their orbits would eventually be disrupted, and as a result they would collide with a positively charged nucleus. However, inside atoms this usually does not happen. Indeed, electronic "orbits" are surprisingly stable over a wide range of conditions.
In addition, experiments with "excited" atoms have shown that electromagnetic energy is emitted by an atom only at certain frequencies. Atoms are "excited" by external influences such as light, known to absorb energy and return electromagnetic waves at certain frequencies, much like a tuning fork that does not ring at a certain frequency until it is struck. When the light emitted by an excited atom is divided by a prism into its component frequencies (colors), individual lines of colors in the spectrum are found, the spectral line pattern is unique to a chemical element. This phenomenon is commonly used to identify chemical elements, and even to measure the proportions of each element in a compound or chemical mixture. According to the solar system of the Rutherford atomic model (relative to electrons, as pieces of matter, freely rotating in an orbit with some radius) and the laws of classical physics, excited atoms must return energy in an almost infinite frequency range, and not at selected frequencies. In other words, if Rutherford's model was correct, then there would be no "tuning fork" effect, and the color spectrum emitted by any atom would appear as a continuous band of colors, rather than as several separate lines.
Bohr's model of the hydrogen atom (with the orbits drawn to scale) assumes that electrons are only in discrete orbits. Electrons moving from n=3,4,5 or 6 to n=2 are displayed on a series of Balmer spectral lines A researcher named Niels Bohr tried to improve Rutherford's model after studying it in Rutherford's laboratory for several months in 1912. Trying to reconcile the results of other physicists (in particular, Max Planck and Albert Einstein), Bohr suggested that each electron had a certain, specific amount of energy, and that their orbits were distributed in such a way that each of them could occupy certain places around the nucleus, like balls. , fixed on circular paths around the nucleus, and not as free-moving satellites, as previously assumed (figure above). In deference to the laws of electromagnetism and accelerating charges, Bohr referred to "orbits" as stationary states to avoid the interpretation that they were mobile.
Although Bohr's ambitious attempt to rethink the structure of the atom, which was more consistent with experimental data, was a milestone in physics, it was not completed. His mathematical analysis predicted the results of experiments better than those performed according to previous models, but there were still unanswered questions about whether Why the electrons must behave in such a strange way. The statement that electrons existed in stationary quantum states around the nucleus correlated better with experimental data than Rutherford's model, but did not say what causes the electrons to take on these special states. The answer to this question was to come from another physicist, Louis de Broglie, some ten years later.
De Broglie suggested that electrons, like photons (particles of light), have both the properties of particles and the properties of waves. Based on this assumption, he suggested that the analysis of rotating electrons in terms of waves is better than in terms of particles, and can give more insight into their quantum nature. Indeed, another breakthrough was made in understanding.
A string vibrating at a resonant frequency between two fixed points forms a standing wave The atom, according to de Broglie, consisted of standing waves, a phenomenon well known to physicists in various forms. Like the plucked string of a musical instrument (pictured above), vibrating at a resonant frequency, with "knots" and "anti-knots" in stable places along its length. De Broglie imagined electrons around atoms as waves curved into a circle (figure below).
"Rotating" electrons like a standing wave around the nucleus, (a) two cycles in an orbit, (b) three cycles in an orbit Electrons can only exist in certain, specific "orbits" around the nucleus, because they are the only distances where the ends of the wave coincide. At any other radius, the wave will collide destructively with itself and thus cease to exist.
De Broglie's hypothesis provided both a mathematical framework and a convenient physical analogy to explain the quantum states of electrons within an atom, but his model of the atom was still incomplete. For several years, physicists Werner Heisenberg and Erwin Schrödinger, working independently, have been working on de Broglie's concept of wave-particle duality in order to create more rigorous mathematical models of subatomic particles.
This theoretical advance from de Broglie's primitive standing wave model to models of the Heisenberg matrix and the Schrödinger differential equation has been given the name of quantum mechanics, and it has introduced a rather shocking feature into the world of subatomic particles: the sign of probability, or uncertainty. According to the new quantum theory, it was impossible to determine the exact position and exact momentum of a particle at one moment. A popular explanation for this "uncertainty principle" was that there was a measurement error (that is, by trying to accurately measure the position of an electron, you interfere with its momentum, and therefore cannot know what it was before you started measuring the position, and vice versa). The sensational conclusion of quantum mechanics is that particles do not have exact positions and momenta, and because of the relationship of these two quantities, their combined uncertainty will never decrease below a certain minimum value.
This form of "uncertainty" connection also exists in fields other than quantum mechanics. As discussed in the "Mixed Frequency AC Signals" chapter in Volume 2 of this book series, there are mutually exclusive relationships between the confidence in the time domain data of a waveform and its frequency domain data. Simply put, the more we know its component frequencies, the less accurately we know its amplitude over time, and vice versa. Quoting myself:
A signal of infinite duration (an infinite number of cycles) can be analyzed with absolute accuracy, but the fewer cycles available to the computer for analysis, the less accurate the analysis ... The fewer periods of the signal, the less accurate its frequency. Taking this concept to its logical extreme, a short pulse (not even a full period of a signal) doesn't really have a defined frequency, it's an infinite range of frequencies. This principle is common to all wave phenomena, and not only to variable voltages and currents.
To accurately determine the amplitude of a changing signal, we must measure it in a very short amount of time. However, doing this limits our knowledge of the frequency of the wave (a wave in quantum mechanics does not need to be similar to a sine wave; such similarity is a special case). On the other hand, in order to determine the frequency of a wave with great accuracy, we must measure it over a large number of periods, which means that we will lose sight of its amplitude at any given moment. Thus, we cannot simultaneously know the instantaneous amplitude and all frequencies of any wave with unlimited accuracy. Another oddity, this uncertainty is much greater than the inaccuracy of the observer; it is in the very nature of the wave. This is not the case, although it would be possible, given the appropriate technology, to provide accurate measurements of both instantaneous amplitude and frequency simultaneously. In a literal sense, a wave cannot have the exact instantaneous amplitude and the exact frequency at the same time.
The minimum uncertainty of particle position and momentum expressed by Heisenberg and Schrödinger has nothing to do with a limitation in measurement; rather, it is an intrinsic property of the nature of the wave-particle duality of the particle. Therefore, electrons do not actually exist in their "orbits" as well-defined particles of matter, or even as well-defined waveforms, but rather as "clouds" - a technical term. wave function probability distributions, as if each electron were "scattered" or "smeared out" over a range of positions and momenta.
This radical view of electrons as indeterminate clouds initially contradicts the original principle of the quantum states of electrons: electrons exist in discrete, definite "orbits" around the nucleus of an atom. This new view, after all, was the discovery that led to the formation and explanation of quantum theory. How strange it seems that a theory created to explain the discrete behavior of electrons ends up declaring that electrons exist as "clouds" and not as separate pieces of matter. However, the quantum behavior of electrons does not depend on electrons having certain values of coordinates and momentum, but on other properties called quantum numbers. In essence, quantum mechanics dispenses with the common concepts of absolute position and absolute moment, and replaces them with absolute concepts of types that have no analogues in common practice.
Even though electrons are known to exist in disembodied, "cloudy" forms of distributed probability, rather than separate pieces of matter, these "clouds" have slightly different characteristics. Any electron in an atom can be described by four numerical measures (the quantum numbers mentioned earlier), called main (radial), orbital (azimuth), magnetic And spin numbers. Below is a brief overview of the meaning of each of these numbers:
Principal (radial) quantum number: denoted by a letter n, this number describes the shell on which the electron resides. The electron "shell" is a region of space around the nucleus of an atom in which electrons can exist, corresponding to de Broglie and Bohr's stable "standing wave" models. Electrons can "jump" from shell to shell, but cannot exist between them.
The principal quantum number must be a positive integer (greater than or equal to 1). In other words, the principal quantum number of an electron cannot be 1/2 or -3. These integers were not chosen arbitrarily, but through experimental evidence of the light spectrum: the different frequencies (colors) of light emitted by excited hydrogen atoms follow a mathematical relationship depending on specific integer values, as shown in the figure below.
Each shell has the ability to hold multiple electrons. An analogy for electron shells is the concentric rows of seats in an amphitheater. Just as a person sitting in an amphitheater must choose a row to sit down (he cannot sit between the rows), electrons must "choose" a particular shell in order to "sit down". Like rows in an amphitheatre, the outer shells hold more electrons than the shells closer to the center. Also, the electrons tend to find the smallest available shell, just as people in an amphitheater look for the place closest to the central stage. The higher the shell number, the more energy the electrons have on it.
The maximum number of electrons that any shell can hold is described by the equation 2n 2 , where n is the principal quantum number. Thus, the first shell (n = 1) can contain 2 electrons; the second shell (n = 2) - 8 electrons; and the third shell (n = 3) - 18 electrons (figure below).
The main quantum number n and the maximum number of electrons are related by the formula 2(n 2). Orbits are not to scale. The electron shells in the atom were denoted by letters rather than numbers. The first shell (n = 1) was designated K, the second shell (n = 2) L, the third shell (n = 3) M, the fourth shell (n = 4) N, the fifth shell (n = 5) O, the sixth shell ( n = 6) P, and the seventh shell (n = 7) B.
Orbital (azimuth) quantum number: a shell composed of subshells. Some may find it more convenient to think of subshells as simple sections of shells, like lanes dividing a road. Subshells are much weirder. Subshells are regions of space where electron "clouds" can exist, and in fact different subshells have different shapes. The first subshell is in the shape of a ball (Figure below (s)), which makes sense when visualized as an electron cloud surrounding the nucleus of an atom in three dimensions.
The second subshell resembles a dumbbell, consisting of two "petals" connected at one point near the center of the atom (figure below (p)).
The third subshell usually resembles a set of four "petals" grouped around the nucleus of an atom. These subshell shapes resemble graphical antenna patterns with bulbous lobes extending from the antenna in various directions (Figure below (d)).
Orbitals: (s) triple symmetry;
(p) Shown: p x , one of three possible orientations (p x , p y , p z), along the respective axes;
(d) Shown: d x 2 -y 2 is similar to d xy , d yz , d xz . Shown: d z 2 . Number of possible d-orbitals: five.
Valid values for the orbital quantum number are positive integers, as for the principal quantum number, but also include zero. These quantum numbers for electrons are denoted by the letter l. The number of subshells is equal to the principal quantum number of the shell. Thus, the first shell (n = 1) has one subshell with number 0; the second shell (n = 2) has two subshells numbered 0 and 1; the third shell (n = 3) has three subshells numbered 0, 1 and 2.
The old subshell convention used letters rather than numbers. In this format, the first subshell (l = 0) was denoted s, the second subshell (l = 1) was denoted p, the third subshell (l = 2) was denoted d, and the fourth subshell (l = 3) was denoted f. The letters came from the words: sharp, principal, diffuse And Fundamental. You can still see these designations in many periodic tables used to denote the electron configuration of the outer ( valence) shells of atoms.
(a) the Bohr representation of the silver atom, (b) Orbital representation of Ag with division of shells into subshells (orbital quantum number l).
This diagram does not imply anything about the actual position of the electrons, but only represents the energy levels.
Magnetic quantum number: The magnetic quantum number for the electron classifies the orientation of the electron subshell figure. The "petals" of the subshells can be directed in several directions. These different orientations are called orbitals. For the first subshell (s; l = 0), which resembles a sphere, "direction" is not specified. For a second (p; l = 1) subshell in each shell that resembles a dumbbell pointing in three possible directions. Imagine three dumbbells intersecting at the origin, each pointing along its own axis in a triaxial coordinate system.
Valid values for a given quantum number consist of integers ranging from -l to l, and this number is denoted as m l in atomic physics and z in nuclear physics. To calculate the number of orbitals in any subshell, you need to double the number of the subshell and add 1, (2∙l + 1). For example, the first subshell (l = 0) in any shell contains one orbital numbered 0; the second subshell (l = 1) in any shell contains three orbitals with numbers -1, 0 and 1; the third subshell (l = 2) contains five orbitals numbered -2, -1, 0, 1 and 2; and so on.
Like the principal quantum number, the magnetic quantum number arose directly from experimental data: the Zeeman effect, the separation of spectral lines by exposing an ionized gas to a magnetic field, hence the name "magnetic" quantum number.
Spin quantum number: like the magnetic quantum number, this property of the electrons of an atom was discovered through experiments. Careful observation of the spectral lines showed that each line was in fact a pair of very closely spaced lines, it has been suggested that this so-called fine structure was the result of each electron "spinning" around its own axis, like a planet. Electrons with different "spins" would give off slightly different frequencies of light when excited. The spinning electron concept is now obsolete, being more appropriate for the (incorrect) view of electrons as individual particles of matter rather than as "clouds", but the name remains.
Spin quantum numbers are denoted as m s in atomic physics and sz in nuclear physics. Each orbital in each subshell can have two electrons in each shell, one with spin +1/2 and the other with spin -1/2.
Physicist Wolfgang Pauli developed a principle that explains the ordering of electrons in an atom according to these quantum numbers. His principle, called Pauli exclusion principle, states that two electrons in the same atom cannot occupy the same quantum states. That is, each electron in an atom has a unique set of quantum numbers. This limits the number of electrons that can occupy any given orbital, subshell, and shell.
This shows the arrangement of electrons in a hydrogen atom:
With one proton in the nucleus, the atom accepts one electron for its electrostatic balance (the proton's positive charge is exactly balanced by the electron's negative charge). This electron is located in the lower shell (n = 1), the first subshell (l = 0), in the only orbital (spatial orientation) of this subshell (m l = 0), with a spin value of 1/2. The general method of describing this structure is by enumerating the electrons according to their shells and subshells, according to a convention called spectroscopic notation. In this notation, the shell number is shown as an integer, the subshell as a letter (s,p,d,f), and the total number of electrons in the subshell (all orbitals, all spins) as a superscript. Thus, hydrogen, with its single electron placed at the base level, is described as 1s 1 .
Moving on to the next atom (in order of atomic number), we get the element helium:
A helium atom has two protons in its nucleus, which requires two electrons to balance the double positive electrical charge. Since two electrons - one with spin 1/2 and the other with spin -1/2 - are in the same orbital, the electronic structure of helium does not require additional subshells or shells to hold the second electron.
However, an atom requiring three or more electrons will need additional subshells to hold all the electrons, since only two electrons can be on the bottom shell (n = 1). Consider the next atom in the sequence of increasing atomic numbers, lithium:
The lithium atom uses part of the capacitance L of the shell (n = 2). This shell actually has a total capacity of eight electrons (maximum shell capacity = 2n 2 electrons). If we consider the structure of an atom with a completely filled L shell, we see how all combinations of subshells, orbitals, and spins are occupied by electrons:
Often, when assigning a spectroscopic notation to an atom, any fully filled shells are skipped, and unfilled shells and top-level filled shells are denoted. For example, the element neon (shown in the figure above), which has two completely filled shells, can be described spectrally simply as 2p 6 rather than as 1s 22 s 22 p 6 . Lithium, with its fully filled K shell and a single electron in the L shell, can simply be described as 2s 1 rather than 1s 22 s 1 .
The omission of fully populated lower-level shells is not only for convenience of notation. It also illustrates a basic principle of chemistry: the chemical behavior of an element is primarily determined by its unfilled shells. Both hydrogen and lithium have one electron on their outer shells (as 1 and 2s 1, respectively), that is, both elements have similar properties. Both are highly reactive, and react in almost identical ways (binding to similar elements under similar conditions). It doesn't really matter that lithium has a fully filled K-shell under an almost free L-shell: the unfilled L-shell is the one that determines its chemical behavior.
Elements that have completely filled outer shells are classified as noble and are characterized by an almost complete lack of reaction with other elements. These elements were classified as inert when they were considered not to react at all, but they are known to form compounds with other elements under certain conditions.
Since elements with the same configuration of electrons in their outer shells have similar chemical properties, Dmitri Mendeleev organized the chemical elements in a table accordingly. This table is known as , and modern tables follow this general layout, shown in the figure below.
Periodic table of chemical elements Dmitri Mendeleev, a Russian chemist, was the first to develop the periodic table of elements. Even though Mendeleev organized his table according to atomic mass rather than atomic number, and created a table that was not as useful as modern periodic tables, his development stands as an excellent example of scientific proof. Seeing patterns of periodicity (similar chemical properties according to atomic mass), Mendeleev hypothesized that all elements must fit into this ordered pattern. When he discovered "empty" places in the table, he followed the logic of the existing order and assumed the existence of yet unknown elements. The subsequent discovery of these elements confirmed the scientific correctness of Mendeleev's hypothesis, further discoveries led to the form of the periodic table that we use now.
Like this must work science: hypotheses lead to logical conclusions and are accepted, changed or rejected depending on the consistency of experimental data with their conclusions. Any fool can formulate a hypothesis after the fact to explain the available experimental data, and many do. What distinguishes a scientific hypothesis from post hoc speculation is the prediction of future experimental data that has not yet been collected, and possibly the refutation of that data as a result. Boldly lead the hypothesis to its logical conclusion(s) and the attempt to predict the results of future experiments is not a dogmatic leap of faith, but rather a public test of this hypothesis, an open challenge to the opponents of the hypothesis. In other words, scientific hypotheses are always "risky" because of trying to predict the results of experiments that have not yet been done, and therefore can be falsified if the experiments do not go as expected. Thus, if a hypothesis correctly predicts the results of repeated experiments, it is disproven.
Quantum mechanics, first as a hypothesis and then as a theory, has been extremely successful in predicting the results of experiments, and hence has received a high degree of scientific credibility. Many scientists have reason to believe that this is an incomplete theory, since its predictions are more true at microphysical scales than macroscopic ones, but nevertheless, it is an extremely useful theory for explaining and predicting the interaction of particles and atoms.
As you have seen in this chapter, quantum physics is essential in describing and predicting many different phenomena. In the next section, we will see its significance in the electrical conductivity of solids, including semiconductors. Simply put, nothing in chemistry or solid state physics makes sense in the popular theoretical structure of electrons existing as individual particles of matter circling around the nucleus of an atom like miniature satellites. When electrons are viewed as "wave functions" existing in certain, discrete states that are regular and periodic, then the behavior of matter can be explained.
Summing up
The electrons in atoms exist in "clouds" of distributed probability, and not as discrete particles of matter revolving around the nucleus, like miniature satellites, as common examples show.
Individual electrons around the nucleus of an atom tend to unique "states" described by four quantum numbers: principal (radial) quantum number, known as shell; orbital (azimuth) quantum number, known as subshell; magnetic quantum number describing orbital(subshell orientation); And spin quantum number, or simply spin. These states are quantum, that is, “between them” there are no conditions for the existence of an electron, except for states that fit into the quantum numbering scheme.
Glanoe (radial) quantum number (n) describes the base level or shell in which the electron resides. The greater this number, the greater the radius of the electron cloud from the nucleus of the atom, and the greater the energy of the electron. Principal quantum numbers are integers (positive integers)
Orbital (azimuthal) quantum number (l) describes the shape of an electron cloud in a particular shell or level and is often known as a "subshell". In any shell, there are as many subshells (forms of an electron cloud) as the main quantum number of the shell. Azimuthal quantum numbers are positive integers starting from zero and ending with a number less than the main quantum number by one (n - 1).
Magnetic quantum number (m l) describes what orientation the subshell (electron cloud shape) has. Subshells can have as many different orientations as twice the subshell number (l) plus 1, (2l+1) (that is, for l=1, m l = -1, 0, 1), and each unique orientation is called an orbital. These numbers are integers starting from a negative value of the subshell number (l) through 0 and ending with a positive value of the subshell number.
Spin Quantum Number (m s) describes another property of the electron and can take the values +1/2 and -1/2.
Pauli exclusion principle says that two electrons in an atom cannot share the same set of quantum numbers. Therefore, there can be at most two electrons in each orbital (spin=1/2 and spin=-1/2), 2l+1 orbitals in each subshell, and n subshells in each shell, and no more.
Spectroscopic notation is a convention for the electronic structure of an atom. Shells are shown as integers, followed by subshell letters (s, p, d, f) with superscript numbers indicating the total number of electrons found in each respective subshell.
The chemical behavior of an atom is determined solely by electrons in unfilled shells. Low-level shells that are completely filled have little or no effect on the chemical binding characteristics of the elements.
Elements with completely filled electron shells are almost completely inert, and are called noble elements (previously known as inert).
Hello dear readers. If you do not want to lag behind life, you want to become a truly happy and healthy person, you should know about the secrets of quantum modern physics, at least have a little idea of what depths of the universe scientists have dug out today. You have no time to go into deep scientific details, but you want to comprehend only the essence, but to see the beauty of the unknown world, then this article: quantum physics for ordinary dummies or, one might say, for housewives, is just for you. I will try to explain what quantum physics is, but in simple words, to show clearly.
"What is the connection between happiness, health and quantum physics?" you ask.
The fact is that it helps to answer many incomprehensible questions related to human consciousness, the influence of consciousness on the body. Unfortunately, medicine, relying on classical physics, does not always help us to be healthy. And psychology can't properly tell you how to find happiness.
Only deeper knowledge of the world will help us understand how to truly cope with illness and where happiness lives. This knowledge is found in the deep layers of the universe. Quantum physics comes to the rescue. Soon you will know everything.
What does quantum physics study in simple words
Yes, indeed, quantum physics is very difficult to understand because it studies the laws of the microworld. That is, the world at its deeper layers, at very small distances, where it is very difficult for a person to look.
And the world, it turns out, behaves there very strangely, mysteriously and incomprehensibly, not as we are used to.
Hence all the complexity and misunderstanding of quantum physics.
But after reading this article, you will expand the horizons of your knowledge and look at the world in a completely different way.
Briefly about the history of quantum physics
It all started at the beginning of the 20th century, when Newtonian physics could not explain many things and scientists reached a dead end. Then Max Planck introduced the concept of quantum. Albert Einstein picked up this idea and proved that light does not propagate continuously, but in portions - quanta (photons). Prior to this, it was believed that light has a wave nature.
But as it turned out later, any elementary particle is not only a quantum, that is, a solid particle, but also a wave. This is how corpuscular-wave dualism appeared in quantum physics, the first paradox and the beginning of discoveries of mysterious phenomena of the microworld.
The most interesting paradoxes began when the famous double-slit experiment was carried out, after which the mysteries became much more. We can say that quantum physics began with him. Let's take a look at it.
Double slit experiment in quantum physics
Imagine a plate with two slots in the form of vertical stripes. We will put a screen behind this plate. If we direct light onto the plate, then we will see an interference pattern on the screen. That is, alternating dark and bright vertical stripes. Interference is the result of the wave behavior of something, in our case light.
If you pass a wave of water through two holes located side by side, you will understand what interference is. That is, the light turns out to be sort of like it has a wave nature. But as physics, or rather Einstein, has proven, it is propagated by photon particles. Already a paradox. But it's okay, corpuscular-wave dualism will no longer surprise us. Quantum physics tells us that light behaves like a wave but is made up of photons. But the miracles are just beginning.
Let's put a gun in front of a plate with two slots, which will emit not light, but electrons. Let's start shooting electrons. What will we see on the screen behind the plate?
After all, electrons are particles, which means that the flow of electrons, passing through two slits, should leave only two stripes on the screen, two traces opposite the slits. Have you imagined pebbles flying through two slots and hitting the screen?
But what do we really see? All the same interference pattern. What is the conclusion: electrons propagate in waves. So electrons are waves. But after all it is an elementary particle. Again corpuscular-wave dualism in physics.
But we can assume that at a deeper level, an electron is a particle, and when these particles come together, they begin to behave like waves. For example, a sea wave is a wave, but it is made up of water droplets, and on a smaller level, molecules, and then atoms. Okay, the logic is solid.
Then let's shoot from a gun not with a stream of electrons, but let's release electrons separately, after a certain period of time. As if we were passing through the cracks not a sea wave, but spitting individual drops from a children's water gun.
It is quite logical that in this case different drops of water would fall into different slots. On the screen behind the plate, one could see not an interference pattern from the wave, but two distinct impact fringes opposite each slit. We will see the same thing if we throw small stones, they, flying through two cracks, would leave a trace, like a shadow from two holes. Let's now shoot individual electrons to see these two stripes on the screen from electron impacts. They released one, waited, the second, waited, and so on. Quantum physicists have been able to do such an experiment.
But horror. Instead of these two fringes, the same interference alternations of several fringes are obtained. How so? This can happen if an electron flies through two slits at the same time, and behind the plate, like a wave, it collides with itself and interferes. But this cannot be, because a particle cannot be in two places at the same time. It either flies through the first slot or through the second.
This is where the truly fantastic things of quantum physics begin.
Superposition in quantum physics
With a deeper analysis, scientists find out that any elementary quantum particle or the same light (photon) can actually be in several places at the same time. And these are not miracles, but the real facts of the microcosm. This is what quantum physics says. That is why, when shooting a separate particle from a cannon, we see the result of interference. Behind the plate, the electron collides with itself and creates an interference pattern.
Ordinary objects of the macrocosm are always in one place, have one state. For example, you are now sitting on a chair, weigh, say, 50 kg, have a pulse rate of 60 beats per minute. Of course, these indications will change, but they will change after some time. After all, you cannot be at home and at work at the same time, weighing 50 and 100 kg. All this is understandable, this is common sense.
In the physics of the microcosm, everything is different.
Quantum mechanics asserts, and this has already been confirmed experimentally, that any elementary particle can be simultaneously not only at several points in space, but also have several states at the same time, such as spin.
All this does not fit into the head, undermines the usual idea of the world, the old laws of physics, turns thinking, one can safely say it drives you crazy.
This is how we come to understand the term "superposition" in quantum mechanics.
Superposition means that an object of the microcosm can simultaneously be in different points of space, and also have several states at the same time. And this is normal for elementary particles. Such is the law of the microworld, no matter how strange and fantastic it may seem.
You are surprised, but these are only flowers, the most inexplicable miracles, mysteries and paradoxes of quantum physics are yet to come.
Wave function collapse in physics in simple terms
Then the scientists decided to find out and see more precisely whether the electron actually passes through both slits. All of a sudden it goes through one slit and then somehow separates and creates an interference pattern as it passes through. Well, you never know. That is, you need to put some device near the slit, which would accurately record the passage of an electron through it. No sooner said than done. Of course, this is difficult to implement, you need not a device, but something else to see the passage of an electron. But scientists have done it.
But in the end, the result stunned everyone.
As soon as we start looking through which slit an electron passes through, it begins to behave not like a wave, not like a strange substance that is located at different points in space at the same time, but like an ordinary particle. That is, it begins to show the specific properties of a quantum: it is located only in one place, it passes through one slot, it has one spin value. What appears on the screen is not an interference pattern, but a simple trace opposite the slit.
But how is that possible. As if the electron is joking, playing with us. At first, it behaves like a wave, and then, after we decided to look at its passage through a slit, it exhibits the properties of a solid particle and passes through only one slit. But that's the way it is in the microcosm. These are the laws of quantum physics.
Scientists have seen another mysterious property of elementary particles. This is how the concepts of uncertainty and collapse of the wave function appeared in quantum physics.
When an electron flies towards the gap, it is in an indefinite state or, as we said above, in a superposition. That is, it behaves like a wave, it is located simultaneously at different points in space, it has two spin values \u200b\u200b(a spin has only two values). If we didn’t touch it, didn’t try to look at it, didn’t find out exactly where it is, if we didn’t measure the value of its spin, it would fly like a wave through two slits at the same time, which means it would create an interference pattern. Quantum physics describes its trajectory and parameters using the wave function.
After we have made a measurement (and it is possible to measure a particle of the microworld only by interacting with it, for example, by colliding another particle with it), then the wave function collapses.
That is, now the electron is exactly in one place in space, has one spin value.
One can say that an elementary particle is like a ghost, it seems to exist, but at the same time it is not in one place, and with a certain probability it can be anywhere within the description of the wave function. But as soon as we begin to contact it, it turns from a ghostly object into a real tangible substance that behaves like ordinary objects of the classical world that are familiar to us.
"This is fantastic," you say. Sure, but the wonders of quantum physics are just beginning. The most incredible is yet to come. But let's take a break from the abundance of information and return to quantum adventures another time, in another article. In the meantime, reflect on what you learned today. What can such miracles lead to? After all, they surround us, this is a property of our world, albeit at a deeper level. Do we still think we live in a boring world? But we will draw conclusions later.
I tried to talk about the basics of quantum physics briefly and clearly.
But if you don’t understand something, then watch this cartoon about quantum physics, about the experiment with two slits, everything is also told there in an understandable, simple language.
Cartoon about quantum physics:
Or you can watch this video, everything will fall into place, quantum physics is very interesting.
Video about quantum physics:
How did you not know about this before?
Modern discoveries in quantum physics are changing our familiar material world.
Quantum physics has radically changed our understanding of the world. According to quantum physics, we can influence the process of rejuvenation with our consciousness!
Why is this possible?From the point of view of quantum physics, our reality is a source of pure potentialities, a source of raw materials that make up our body, our mind and the entire Universe. The universal energy and information field never stops changing and transforming, turning into something new every second.
In the 20th century, during physical experiments with subatomic particles and photons, it was discovered that the fact of observing the course of an experiment changes its results. What we focus our attention on can react.
This fact is confirmed by a classic experiment that surprises scientists every time. It was repeated in many laboratories and the same results were always obtained.
For this experiment, a light source and a screen with two slits were prepared. As a light source, a device was used that "shot" photons in the form of single pulses.
The course of the experiment was monitored. After the end of the experiment, two vertical stripes were visible on the photographic paper that was behind the slits. These are traces of photons that passed through the slits and illuminated the photographic paper.
When this experiment was repeated in automatic mode, without human intervention, the picture on photographic paper changed:
If the researcher turned on the device and left, and after 20 minutes the photographic paper developed, then not two, but many vertical stripes were found on it. These were traces of radiation. But the drawing was different.
The structure of the trace on photographic paper resembled the trace of a wave that passed through the slits. Light can exhibit the properties of a wave or a particle.
As a result of the simple fact of observation, the wave disappears and turns into particles. If you do not observe, then a trace of the wave appears on the photographic paper. This physical phenomenon is called the Observer Effect.
The same results were obtained with other particles. The experiments were repeated many times, but each time they surprised scientists. So it was discovered that at the quantum level, matter reacts to the attention of a person. This was new in physics.
According to the concepts of modern physics, everything materializes from the void. This emptiness is called "quantum field", "zero field" or "matrix". The void contains energy that can turn into matter.
Matter consists of concentrated energy - this is the fundamental discovery of physics of the 20th century.
There are no solid parts in an atom. Objects are made up of atoms. But why are objects solid? A finger attached to a brick wall does not pass through it. Why? This is due to differences in the frequency characteristics of atoms and electric charges. Each type of atom has its own vibration frequency. This determines the differences in the physical properties of objects. If it were possible to change the vibration frequency of the atoms that make up the body, then a person could pass through the walls. But the vibrational frequencies of the atoms of the hand and the atoms of the wall are close. Therefore, the finger rests on the wall.
For any kind of interaction, frequency resonance is necessary.
This is easy to understand with a simple example. If you illuminate a stone wall with the light of a flashlight, the light will be blocked by the wall. However, mobile phone radiation will easily pass through this wall. It's all about the frequency differences between the radiation of a flashlight and a mobile phone. While you are reading this text, streams of very different radiation are passing through your body. These are cosmic radiation, radio signals, signals from millions of mobile phones, radiation coming from the earth, solar radiation, radiation created by household appliances, etc.
You don't feel it because you can only see light and hear only sound. Even if you sit in silence with your eyes closed, millions of telephone conversations, pictures of television news and radio messages go through your head. You do not perceive this, because there is no resonance of frequencies between the atoms that make up your body and radiation. But if there is a resonance, then you immediately react. For example, when you remember a loved one who just thought of you. Everything in the universe obeys the laws of resonance.
The world consists of energy and information. Einstein, after much thought about the structure of the world, said: "The only reality that exists in the universe is the field." Just as waves are a creation of the sea, all manifestations of matter: organisms, planets, stars, galaxies are creations of the field.
The question arises, how is matter created from the field? What force controls the motion of matter?
Research scientists led them to an unexpected answer. The founder of quantum physics, Max Planck, said the following during his Nobel Prize speech:
“Everything in the Universe is created and exists due to force. We must assume that behind this force is a conscious mind, which is the matrix of all matter.
MATTER IS GOVERNED BY CONSCIOUSNESS
At the turn of the 20th and 21st centuries, new ideas appeared in theoretical physics that make it possible to explain the strange properties of elementary particles. Particles can appear from the void and suddenly disappear. Scientists admit the possibility of the existence of parallel universes. Perhaps particles move from one layer of the universe to another. Celebrities such as Stephen Hawking, Edward Witten, Juan Maldacena, Leonard Susskind are involved in the development of these ideas.
According to the concepts of theoretical physics, the Universe resembles a nesting doll, which consists of many nesting dolls - layers. These are variants of universes - parallel worlds. The ones next to each other are very similar. But the further the layers are from each other, the less similarities between them. Theoretically, in order to move from one universe to another, spaceships are not required. All possible options are located one inside the other. For the first time these ideas were expressed by scientists in the middle of the 20th century. At the turn of the 20th and 21st centuries, they received mathematical confirmation. Today, such information is easily accepted by the public. However, a couple of hundred years ago, for such statements they could be burned at the stake or declared crazy.
Everything arises from emptiness. Everything is in motion. Items are an illusion. Matter is made up of energy. Everything is created by thought. These discoveries of quantum physics contain nothing new. All this was known to the ancient sages. In many mystical teachings, which were considered secret and were available only to initiates, it was said that there was no difference between thoughts and objects.Everything in the world is filled with energy. The universe responds to thought. Energy follows attention.
What you focus your attention on begins to change. These thoughts in various formulations are given in the Bible, ancient Gnostic texts, in mystical teachings that originated in India and South America. The builders of the ancient pyramids guessed this. This knowledge is the key to the new technologies that are being used today to manipulate reality.
Our body is a field of energy, information and intelligence, which is in a state of constant dynamic exchange with the environment. The impulses of the mind constantly, every second, give the body new forms to adapt to the changing demands of life.
From the point of view of quantum physics, our physical body, under the influence of our mind, is able to make a quantum leap from one biological age to another without going through all the intermediate ages. published
P.S. And remember, just by changing your consumption, we are changing the world together! © econet
From the Greek "fusis" comes the word "physics". It means "nature". Aristotle, who lived in the fourth century BC, first introduced this concept.
Physics became "Russian" at the suggestion of M.V. Lomonosov, when he translated the first textbook from German.
science physics
Physics is one of the main ones. Various processes, changes, that is, phenomena are constantly taking place around the world.
For example, a piece of ice in a warm place will begin to melt. And the water in the kettle boils on fire. An electric current passed through the wire will heat it up and even make it hot. Each of these processes is a phenomenon. In physics, these are mechanical, magnetic, electrical, sound, thermal and light changes that are studied by science. They are also called physical phenomena. Considering them, scientists deduce laws.
The task of science is to discover these laws and study them. Nature is studied by such sciences as biology, geography, chemistry and astronomy. They all apply physical laws.
Terms
In addition to the usual ones in physics, they also use special words called terms. These are “energy” (in physics it is a measure of different forms of interaction and movement of matter, as well as the transition from one to another), “force” (a measure of the intensity of the influence of other bodies and fields on a body) and many others. Some of them gradually entered into colloquial speech.
For example, using the word "energy" in everyday life in relation to a person, we can evaluate the consequences of his actions, but energy in physics is a measure of study in many different ways.
All bodies in physics are called physical. They have volume and shape. They consist of substances, which, in turn, are one of the types of matter - this is everything that exists in the Universe.
Experiences
Much of what people know has come from observations. To study phenomena, they are constantly observed.
Take, for example, various bodies falling to the ground. It is necessary to find out whether this phenomenon differs when falling bodies of unequal masses, different heights, and so on. Waiting and watching different bodies would be very long and not always successful. Therefore, experiments are carried out for such purposes. They differ from observations, as they are specifically implemented according to a predetermined plan and with specific goals. Usually, in the plan, some guesses are built in advance, that is, they put forward hypotheses. Thus, in the course of the experiments, they will be refuted or confirmed. After thinking and explaining the results of the experiments, conclusions are drawn. This is how scientific knowledge is obtained.
Quantities and their units
Often, studying any perform different measurements. When a body falls, for example, height, mass, speed and time are measured. All this is, that is, something that can be measured.
Measuring a value means comparing it with the same value, which is taken as a unit (the length of the table is compared with a unit of length - a meter or another). Each such value has its own units.
All countries try to use uniform units. In Russia, as in other countries, the International System of Units (SI) is used (which means "international system"). It adopts the following units:
- length (characteristic of the length of lines in numerical terms) - meter;
- time (flow of processes, condition of possible change) - second;
- mass (this is a characteristic in physics that determines the inertial and gravitational properties of matter) - kilogram.
It is often necessary to use units that are much larger than the conventional multiples. They are called with the corresponding prefixes from the Greek: “deka”, “hekto”, “kilo” and so on.
Units that are smaller than the accepted ones are called submultiples. Prefixes from the Latin language are applied to them: “deci”, “santi”, “milli” and so on.
Measuring instruments
To conduct experiments, you need equipment. The simplest of them are the ruler, cylinder, tape measure and others. With the development of science, new devices are being improved, complicated and new devices appear: voltmeters, thermometers, stopwatches and others.
Basically, devices have a scale, that is, dashed divisions on which values \u200b\u200bare written. Before measurement, determine the division price:
- take two strokes of the scale with values;
- the smaller is subtracted from the larger, and the resulting number is divided by the number of divisions that are between.
For example, two strokes with the values "twenty" and "thirty", the distance between which is divided into ten spaces. In this case, the division value will be equal to one.
Accurate measurements and with an error
The measurements are more or less accurate. The allowable inaccuracy is called the margin of error. When measuring, it cannot be greater than the division value of the measuring instrument.
Accuracy depends on the scale interval and the correct use of the instrument. But in the end, in any measurement, only approximate values \u200b\u200bare obtained.
Theoretical and experimental physics
These are the main branches of science. It may seem that they are very far apart, especially since most people are either theorists or experimenters. However, they are constantly evolving side by side. Any problem is considered by both theorists and experimenters. The business of the former is to describe the data and derive hypotheses, while the latter test theories in practice, conducting experiments and obtaining new data. Sometimes achievements are caused only by experiments, without theories being described. In other cases, on the contrary, it is possible to obtain results that are checked later.
The quantum physics
This direction originated at the end of 1900, when a new physical fundamental constant was discovered, called the Planck constant in honor of the German physicist who discovered it, Max Planck. He solved the problem of the spectral distribution of light emitted by heated bodies, while classical general physics could not do this. Planck made a hypothesis about the quantum energy of the oscillator, which was incompatible with classical physics. Thanks to it, many physicists began to revise old concepts, change them, as a result of which quantum physics arose. This is a completely new view of the world.
and consciousness
The phenomenon of human consciousness from the point of view is not entirely new. Its foundation was laid by Jung and Pauli. But only now, with the formation of this new direction of science, the phenomenon began to be considered and studied on a larger scale.
The quantum world is many-sided and multidimensional, it has many classical faces and projections.
The two main properties within the framework of the proposed concept are superintuition (that is, obtaining information as if from nowhere) and control of subjective reality. In ordinary consciousness, a person can see only one picture of the world and is not able to consider two at once. Whereas in reality there are a huge number of them. All this together is the quantum world and light.
It is quantum physics that teaches us to see a new reality for a person (although many Eastern religions, as well as magicians, have long possessed such a technique). It is only necessary to change the human consciousness. Now a person is inseparable from the whole world, but the interests of all living things and things are taken into account.
Just then, plunging into a state where he is able to see all the alternatives, he comes to insight, which is the absolute truth.
The principle of life from the point of view of quantum physics is for a person to, among other things, contribute to a better world order.
Kvantinė fizika statusas T sritis fizika atitikmenys: engl. quantum physics vok. Quantenphysik, f rus. quantum physics, f pranc. physique quantique, f … Fizikos terminų žodynas
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