Wolfgang Pauli research presented for the Nobel Prize. Physics and lyrics by Wolfgang Pauli

(1900-1958) Swiss theoretical physicist, founder of quantum mechanics

Wolfgang Pauli was born in Vienna. His father, Joseph Pauli, was a renowned physicist and biochemist, professor at the University of Vienna. The mother of the future scientist, Bertha Pauli, was a renowned writer and theater critic. The godfather of the future scientist was the famous physicist and philosopher Ernst Mach.

As a child, Wolfgang Pauli dreamed of becoming an actor and studied music a lot with his younger sister, who later really chose the acting field. However, on the advice of teachers who noticed the boy's mathematical abilities, he entered the University of Munich, where he studied in a seminar under the guidance of the famous physicist Arnold Sommerfeld. In 1921, the young man graduated from the university.

But Wolfgang Pauli began to seriously engage in science thanks to the chance. An acquaintance of Sommerfeld's mathematics professor Felix Klein asked him to write an article on the theory of relativity for a mathematical encyclopedia published in Germany. Because of his busy schedule, Sommerfeld entrusted Pauli with this job.

He wrote a 250-page "article" which Sommerfeld sent for review to Albert Einstein. After his positive feedback, Pauli defended this work as a master's thesis. Just a year after that, he submitted his doctoral dissertation for defense, after the successful defense of which he went to Göttingen, where he began teaching and research activities.

However, Wolfgang Pauli did not stay in Göttingen for long. In 1922 he moved to Copenhagen and became an assistant to Niels Bohr. There, a young physicist began studying atomic spectra. Studying them, Pauli made important additions to the theory of the atom proposed by N. Bohr. In particular, he came to the conclusion that it would be more correct to speak not about the orbits in which electrons revolve around the atomic nucleus, but about the shells that they form around it.

In addition, Wolfgang Pauli showed that each such shell can contain a strictly defined number of electrons.

After this theoretical model was confirmed by the works of Erwin Schrödinger, Werner Heisenberg and Paul Dirac, it became clear that the work of Wolfgang Pauli opened a new direction in physics, which was called quantum mechanics, and the most important quantum mechanical principle was called the Pauli principle. The young scientist made his discoveries when he was an assistant professor at the University of Hamburg.

In 1928, Wolfgang Pauli left Germany and moved to Switzerland, where he began working at the Zurich Institute of Technology. In 1930, he published an article in which he proved that during the decay of an atomic nucleus, in addition to electrons and neutrons, another unregistered particle should appear. This discovery was confirmed years later, after its discovery by Enrico Fermi, who named it a neutrino.

Wolfgang Pauli spent the years of World War II in the United States. There he was in 1945 and learned that he had won the Nobel Prize in physics. Having received it in 1946, Pauli returned to Switzerland, where he lived until the end of his life.

Having great services in the field of physics, he at the same time enjoyed a reputation as a man who brings various misfortunes. They said that as soon as he appeared in the laboratory, all kinds of breakdowns and accidents began there.

Indeed, everyone who knew Wolfgang Pauli noted his rare inability to do anything with his own hands. All affairs in his house were run by his second wife, Francisca Bertrand. His closest friend and recreation partner was the famous German philosopher Carl Jung.

Wolfgang Pauli entered the history of science not only as a theorist, but also as a thinker who strove to penetrate deeply into the history and philosophy of scientific thought and published a number of important works on this subject.

Austrian-Swiss physicist Wolfgang Ernst Pauli was born in Vienna. His father, Wolfgang Josef Pauli, was a renowned physicist and biochemist, professor of colloidal chemistry at the University of Vienna. His mother, Bertha (nee Schütz) Pauli, was a writer associated with Viennese theater and journalism circles. Hertha, Pauli's younger sister, became an actress and writer. Ernst Mach, the famous physicist and philosopher, was his godfather. In high school in Vienna, Pauli showed extraordinary mathematical ability, however, finding the classroom boring, he switched to studying higher mathematics on his own and therefore immediately read Albert Einstein's just-published work on general relativity.

In 1918 Pauli entered the University of Munich, where he studied under the guidance of the famous physicist Arnold Sommerfeld. At this time, the German mathematician Felix Klein was busy publishing a mathematical encyclopedia. Klein asked Sommerfeld to write a review of Einstein's general and special theory of relativity, and Sommerfeld, in turn, asked 20-year-old Pauli to write this article. He quickly wrote a 250-page article, which Sommerfeld described as "simply masterful," and Einstein praised.

In 1921, after completing his doctoral dissertation on the theory of the hydrogen molecule and receiving his doctorate in the shortest possible time for the university, Pauli went to Göttingen, where he took up scientific research with Max Born and James Frank. At the end of 1922 he worked in Copenhagen as an assistant to Niels Bohr. The work under the direction of Sommerfeld, Born, Frank and Bohr awakened Pauli's interest in a new field of physics - quantum theory, which studied the atom and subatomic particles, and he completely immersed himself in the problems facing physicists in this field.

Although the principles of classical physics have provided a satisfactory explanation of the behavior of macroscopic physical systems, attempts to apply the same principles to atomic-scale phenomena have failed. The nuclear model of the atom, according to which electrons rotated in orbits around the central nucleus, seemed especially complicated. According to the principles of classical physics, orbiting electrons must continuously emit electromagnetic radiation, while losing energy and spiraling closer to the nucleus. In 1913, Bohr suggested that electrons cannot emit radiation continuously, since they must be in their permitted orbits; all intermediate orbits are prohibited. An electron can emit or absorb radiation only by making a quantum leap from one permitted orbit to another.

Bohr's model was based in part on the study of atomic spectra. When an element heats up and turns into a gaseous or vapor state, it emits light with a characteristic spectrum. This spectrum is not a continuous color region like that of the Sun, but consists of a sequence of bright lines of specific wavelengths separated by wider dark areas. Bohr's atomic model explained the essence of atomic spectra: each line represented the light emitted by an atom when electrons move from one permitted orbit to another orbit with a lower energy. Moreover, the model correctly predicted most of the characteristics of the simplest atomic spectrum, the hydrogen spectrum. At the same time, this model was less successful in describing the spectra of more complex atoms.

Two more significant shortcomings of Bohr's model helped Pauli subsequently make his significant contribution to quantum theory. First, this model could not explain some of the subtle details in the hydrogen spectrum. For example, when an atomic gas was placed in a magnetic field, some spectral lines split into several closely spaced lines - an effect first discovered by Peter Zeeman in 1896. More important, however, the stability of the electron orbits was not fully explained. While it was considered obvious that the electrons could not spiral onto the nucleus, continuously emitting radiation, there was no clear reason why they should not descend in jumps, moving from one allowed orbit to another and gathering together in the lowest energy state.

In 1923 Pauli became Assistant Professor of Theoretical Physics at the University of Hamburg. Here, at the beginning of 1925, he was engaged in theoretical studies of the structure of atoms and their behavior in magnetic fields, developing the theory of the Zeeman effect and other types of spectral splitting. He suggested that electrons have a property that Samuel Goudsmit and George Uhlenbeck later called spin, or intrinsic angular momentum. In a magnetic field, the electron spin has two possible orientations: the spin axis can be directed in the same direction as the field, or in the opposite direction. The orbital motion of an electron in an atom defines another axis, which can be oriented in different ways depending on the applied external field. The various possible combinations of spin and orbital orientations are slightly different energetically, which leads to an increase in the number of atomic energy states. Transitions of an electron from each of these sublevels to some other orbit correspond to slightly different wavelengths of light, which explains the fine splitting of spectral lines.

Soon after Pauli introduced this "two-valued" property of the electron, he analytically explained why all the electrons in an atom do not occupy the lowest energy level. In Bohr's model, which he improved, the permissible energy states, or orbits, of electrons in an atom are described by four quantum numbers for each electron. These numbers determine the basic energy level of the electron, its orbital angular momentum, its magnetic moment, and (this was Pauli's contribution) the orientation of its spin. Each of these quantum numbers can take only certain values, moreover, only some combinations of these values are allowed. He formulated a law that became known as the Pauli exclusion principle, according to which no two electrons in a system can have the same set of quantum numbers. So, each shell in an atom can contain only a limited number of electron orbits, determined by the admissible values of quantum numbers.

The Pauli exclusion principle plays a fundamental role in understanding the structure and behavior of atoms, atomic nuclei, the properties of metals and other physical phenomena. He explains the chemical interaction of elements and their previously incomprehensible arrangement in the periodic table. Pauli himself used the exclusion principle in order to understand the magnetic properties of simple metals and some gases.

Soon after Pauli formulated his exclusion principle, quantum theory received a solid theoretical foundation thanks to the work of Erwin Schrödinger, Werner Heisenberg, and P.A.M.Dirac. The theoretical apparatus they used to describe atomic and subatomic systems came to be called quantum mechanics. Bohr's atomic model was replaced by a quantum mechanical model, which was more successful in predicting spectra and other atomic phenomena. Pauli's accomplishments extended quantum mechanics to areas such as high-energy particle physics and the interaction of particles with light and other forms of electromagnetic fields. These areas became known as relativistic quantum electrodynamics.

In 1928, Pauli succeeded Peter Debye as professor at the Federal Institute of Technology in Zurich, where he remained for the rest of his life, with the exception of two periods in the United States; he spent the academic year 1935/36 as a visiting lecturer at the Institute for Basic Research in Princeton, NJ and during World War II, when, fearing that Germany would invade Switzerland, he returned to the same institute where he headed Department of Theoretical Physics from 1940 to 1946

In the 30s. he made another important contribution to physics. Observations of the beta decay of atomic nuclei, in which a neutron in the nucleus emits an electron, turning into a proton, revealed an obvious violation of the energy conservation law: after taking into account all the registered decay products, the energy after decay turned out to be less than its value before decay. In 1930, Pauli put forward a hypothesis according to which it was assumed that during such a decay, some unrecorded particle (which Enrico Fermi called a neutrino) is emitted, carrying away the lost energy, while the law of conservation of angular momentum remained in force. Eventually, neutrinos were detected in 1956.

In 1945 Pauli was awarded the Nobel Prize in Physics "for the discovery of the exclusion principle, which is also called the Pauli exclusion principle." He was not present at the award ceremony, and an employee of the American Embassy in Stockholm received it on his behalf.In the Nobel lecture sent to Stockholm the following year, Pauli summed up his work on the exclusion principle and quantum mechanics.

Pauli became a Swiss citizen in 1946. In his further work, he sought to shed light on the problems of interaction of high-energy particles and the forces with which they interact, i.e. worked in the area of physics that is now called high-energy physics, or particle physics. He also did an in-depth study of the role that symmetry plays in particle physics. Possessing truly fantastic abilities and the ability to penetrate deeply into the essence of physical problems, he was intolerant of vague arguments and superficial judgments. He subjected his own work to such ruthless critique that his publications are virtually free of error. Colleagues called him "the conscience of physics."

After a divorce following a short and unhappy first marriage, Pauli married Francisca Bertram in 1934. With a deep interest in philosophy and psychology, he took great pleasure in conversations with his friend C.G. Jung. He also held art, music and theater in high regard. During his holidays he liked to swim, wander through the mountains and forests of Switzerland. Pauli's intellectual abilities were in sharp dissonance with his "ability" to work with his hands. His colleagues used to joke about the mysterious Pauli effect, when the mere presence of a short and plump scientist in the laboratory seemed to cause all sorts of breakdowns and accidents. In early December 1958, Pauli fell ill and soon, on December 15, died.

In addition to the Nobel Prize, Pauli was awarded the Franklin Franklin Institute Medal (1952) and the Max Planck Medal of the German Physical Society (1958). He was a member of the Swiss Physical Society, the American Physical Society, the American Association for the Basic Sciences, and a foreign member

(58 years old) Place of work

Hamburg University
University of Göttingen
Swiss Higher Technical School of Zurich

Notable students Markus Firz[d], Sigurd zienau[d] and Hans Frauenfelder[d] Awards and prizes Lorenz Medal (1931)
Nobel Prize in Physics ()
Franklin Medal (1952)
Medal of Matteucci (1956)
Max Planck Medal (1958)

Wolfgang Ernst Pauli(German Wolfgang Ernst Pauli; April 25, Vienna - December 15, Zurich) was a Swiss theoretical physicist who worked in the field of particle physics and quantum mechanics. Winner of the Nobel Prize in Physics for 1945.

Biography

Family and early years

Wolfgang Pauli was born in Vienna into the family of the physician and professor of chemistry Wolfgang Josef Pauli (1869-1955), from the prominent Prague Jewish family Pascheles ( Pascheles). In 1898, his father changed his last name to Pauli, and the following year, shortly before his marriage, he converted to the Catholic faith. Wolfgang Pauli's mother is journalist Bertha Camilla Pauli (née Schütz, 1878-1927), daughter of journalist and playwright Friedrich Schütz. The family also had a younger sister, Gert Pauli (1909-1973). Pauli received his second name in honor of his godfather, physicist and philosopher Ernst Mach, who was Pauli's father's teacher in Prague.

In 1910-1918 he studied at the prestigious Vienna Federal Gymnasium Deblinger, where he earned a reputation as a child prodigy. It is said that once in a physics lesson, the teacher made a mistake on the blackboard that he could not find, and in despair called out: “Pauli, finally tell me what the mistake is! You probably found it a long time ago. " Pauli's classmates included the future 1938 Nobel Prize in Chemistry Richard Kuhn.

Education and the beginning of scientific activity

In the fall of 1918, Wolfgang entered the University of Munich, and the famous physicist Arnold Sommerfeld became his mentor. At the request of Sommerfeld, 20-year-old Pauli wrote an extensive review for the Physical Encyclopedia on general relativity, and this monograph remains a classic to this day. Pauli's all-European fame begins with this work. Further, however, the topics of his work concerned mainly the rapidly developing quantum mechanics and related problems of atomic physics. Among Sommerfeld's students was Werner Heisenberg, who became a close friend of Pauli.

In 1921, Pauli defended his dissertation, after which he received an invitation to become an assistant to Max Born and moved to Göttingen. A year later (1922) Pauli taught briefly in Hamburg, then, at the invitation of Niels Bohr, visited him in Copenhagen and intensely discussed with Bohr possible explanations for the anomalous Zeeman effect. In 1923 he returned to Hamburg,

Recognition and recent years

Wolfgang Pauli in the year of the Nobel Prize (1945)

Pauli's finest hour came in 1925, when he discovered a new quantum number (later called spin) and formulated Pauli's fundamental exclusion principle, which explained the structure of the electron shells of atoms.

At the end of the 1920s, there was a severe crisis in Pauli's personal life. In 1927, his mother committed suicide. The father remarried, and his relationship with his son deteriorated markedly. In 1929, Pauli married the ballerina Kat Deppner ( Käthe margarethe deppner), the wife soon went to her old friend, and in 1930 the couple separated. Pauli began to feel depressed, it was then that he began communication with the psychoanalyst Carl Gustav Jung, abruptly broke with the Catholic religion and began to abuse alcohol.

In 1928, Pauli left for Switzerland, where he was appointed professor at the Zurich Higher Technical School. In 1930, Pauli put forward the assumption of the existence of an elementary particle neutrino, which became his second most important contribution to atomic physics. This all-pervading particle was experimentally discovered only 26 years later, during Pauli's lifetime. In the summer of 1931, Pauli visited the United States for the first time, then went to the international congress on nuclear physics in Rome; there, as he recalled with disgust, he had to shake Mussolini's hand.

In 1933 Pauli remarried - to Frank Bertram ( Franziska "Franca" Bertram, 1901-1987), this union turned out to be more successful than the first, although the spouses did not have children.

The remaining 12 years of Pauli's life were devoted to the development of quantum field theory and teaching. Students from many countries came to listen to his lectures, and Pauli himself traveled a lot across Europe with reports and lectures. In 1945, the scientist was awarded the Nobel Prize in Physics, after which (1949) the Swiss authorities recognized him as a Swiss citizen (he received US citizenship only before leaving, in January 1946). Several times (1949, 1953 and 1958) he again visited Princeton (joking "I returned to lose weight"), there he discussed physical problems with those colleagues who did not dare to return to Europe after the war.

In 1958, Pauli was awarded the Max Planck Medal, in December of the same year he died of cancer in Zurich.

Scientific achievements

Pauli made a significant contribution to modern physics, especially to the physics of the microworld. The number of published works by him is relatively small, he always preferred an intensive exchange of letters with his colleagues, especially with close friends Niels Bohr and Werner Heisenberg. For this reason, many of his ideas are found only in these letters, which were often passed on. Nevertheless, his main achievements are widely known:

In 1921, Pauli was the first to propose the "Bohr magneton" as a unit for measuring the magnetic moment.

In 1926, shortly after Heisenberg's publication of the matrix representation of quantum mechanics, Pauli successfully applied this theory to describe the observed spectrum of hydrogen, including the Stark effect. This became a strong argument for the acceptance of Heisenberg's theory. The work of Pauli and Heisenberg in the late 1920s laid the foundation for two new sciences that soon appeared - quantum field theory and solid state physics.

In 1930, Pauli published the hypothesis of the existence of neutrinos. He realized that in the beta decay of a neutron into a proton and an electron, the laws of conservation of energy and momentum can be fulfilled only if another, hitherto unknown particle is emitted. Since at that moment in time it was impossible to prove the existence of this particle, Pauli postulated the existence of an unknown particle. The Italian physicist Enrico Fermi later named this particle "neutron": neutrino. Experimental evidence of the existence of neutrinos appeared only in 1956.

Personal qualities

In the field of physics, Pauli was known as a perfectionist. At the same time, he did not limit himself only to his own works, but also mercilessly criticized the mistakes of his colleagues. He became the "conscience of physics", often referred to the works as "completely incorrect", or commented something like this: "This is not only wrong, it does not even reach the level of error!" In the circles of his colleagues, there was a joke about this: “After Pauli's death, he gets an audience with God. Pauli asks God why the fine structure constant is 1/137. God nods, walks to the blackboard and begins to write equation after equation with terrible speed. Pauli looks at first with great satisfaction, but soon begins to shake his head strongly and decisively.

Pauli was also famous for the fact that in his presence sensitive experimental equipment often suddenly went out of order. This phenomenon is known as the Pauli effect.

Pauli - Jung Dialogue

A lesser known area of his work, which has only been closely studied since 1990, arose from a collaboration with the psychologist Carl Gustav Jung. From their correspondence, which both scientists conducted from 1932 to 1958, it becomes clear that Pauli owns most of the concept of synchronicity, which was introduced by C.G. Jung, and, in addition, part of the clarification of the concepts of the collective unconscious and archetypes, which are of paramount importance. for Jung's works.

An essential part of this dialogue is even today the psychophysical problem that has not yet been resolved, the unification of the collective psycho with matter, the deep roots of the inner world of a person with the outer world, which Jung designated as unus mundus(one world) and Pauli as the psychophysical reality of unity.

The current state of the analysis of his notes shows that Pauli's studies were not only of purely academic interest, but originated from deep-seated personal experiences - existential reflections on the "spirit of matter" archetype.

Awards and memory

1931: Awarded the Lorenz Medal.
1945: in physics.
1950: Elected a Fellow of the American Academy of Arts and Sciences.
1958: Awarded the Max Planck Medal.

Memorial sign in Göttingen

An alley in the 14th district of Vienna ( Wolfgang-Pauli-Gasse) and a street on the Zurich campus ( Wolfgang-Pauli-Strasse). In honor of the scientist, a memorial sign was erected in Göttingen ( Wolfgang-Pauli-Weg).

PAULIE WOLFGANG

(1900 - 1958)

The famous Swiss-Austrian physicist Wolfgang Ernst Pauli was born on April 25, 1900 in Vienna in the family of Wolfgang Joseph Pauli and Bertha Pauli (née Schütz).

The father of the future scientist was a famous physicist and biochemist, professor of colloidal chemistry at the Medical School of the University of Vienna. He came from a Prague Jewish family, but later converted to the Catholic faith. Wolfgang's mother was associated with the Viennese bohemian world, was friends with many theater-goers and journalists, she herself was a master of the pen. Wolfgang Ernst Pauli got his middle name in honor of his god-uncle, physicist and philosopher Ernst Mach.

The children in the Pauli family turned out to be very talented: Wolfgang's younger sister became an actress, and Wolfgang became a world-famous scientist.

Parents sent Wolfgang to study at the federal Vienna gymnasium. Pauli's classmate at the gymnasium was the future Nobel laureate, Richard Kuhn, who received this prize in chemistry in 1938. Pauli's talents in mathematics were already evident in his early years. Soon, having independently studied the gymnasium program, he switched to the study of higher mathematics.

At the gymnasium, Wolfgang became interested in Albert Einstein's work on general relativity. At the age of 18, the future scientist graduated from the gymnasium. By this time, he already had a published article devoted to the problem of the energy of the gravitational field.

In 1918, young Pauli entered the University of Munich, where he studied under the guidance of the famous physicist Arnold Sommerfeld. Sommerfeld was considered the founder of the Munich school of theoretical physics. Upon learning of Pauli's interest in the theory of relativity, he recommended his student to continue research in this area. The very next year, the world saw two works by Pauli, devoted to the possibilities of generalizing the general theory of relativity.

In 1920, Sommerfeld's friend, German mathematician Felix Klein, was preparing the publication of the "Encyclopedia of Mathematical Sciences". Klein asked Sommerfeld to review Einstein's theory of relativity, who in turn instructed 20-year-old Pauli to prepare the paper. After a while, the article lay on Sommerfeld's desk. In it, the author analyzed Einstein's general and special theory of relativity on 250 pages! After reading the article, Sommerfeld described it as "simply masterful." Subsequently, this article-monograph became a classic. It has been published as a separate book many times in various countries.

When the article came to Einstein's eyes, he, praising Pauli, did not know what to be more surprised about - that the author wrote such a mature book at the age of 21, or how deeply he managed to understand the development of an idea and penetration into the physical essence of phenomena.

Since 1920, the young scientist began to take an interest in the microcosm of atoms and spectra. In 1921, under the leadership of Sommerfeld, he successfully defended his doctoral dissertation on the study of the hydrogen molecule, and received his doctorate.

In the same year, Pauli decided to continue his scientific research and learn from the brightest people of that time. He went to Göttingen, where he became Max Born's assistant at the Department of Theoretical Physics at the University of Göttingen. Pauli also worked with James Frank in his laboratory in Göttingen.

At the end of 1922, after working in Switzerland, Pauli moved to Copenhagen, where he became an assistant to the "genius of the era" Niels Bohr at the Institute of Theoretical Physics. In addition to scientific research, Pauli helped Bohr translate his work into German. Bohr's assistant Pauli worked until 1923, when he was offered the position of assistant professor of theoretical physics at the University of Hamburg.

Collaboration with Sommerfeld, Born, Frank and Bohr aroused the young scientist even more interest in the microworld of atoms and subatomic particles - in quantum theory.

In 1924, Pauli formulated one of the most important laws of the physics of the microworld, which bears his name. This was preceded by a number of outstanding discoveries of that time.

After the brilliant physicist Rutherford in 1911 developed the planetary model of the atom, new questions arose concerning the phenomena of atomic problems. According to the postulates of classical physics, electrons located in orbits around the central core must continuously emit electromagnetic radiation. At the same time, they must lose energy and, obeying the attraction of the nucleus, approach it in a spiral.

In 1913, Bohr presented to the world his theory, which said that electrons can only be in certain orbits. As a result, they cannot emit radiation continuously. An electron can move from one of the orbits to another only in the case of a quantum jump.

With the help of Bohr's model, it was possible to predict the characteristic features of the simplest atomic spectra, for example, the spectrum of hydrogen. But it was not possible to apply the model to the description of complex atoms.

Bohr did not provide a clear explanation of the stability of the electron orbits. Although it was clear that electrons cannot spiral onto the nucleus, it is not at all clear why this is impossible as a result of a jump-like transition from one allowed orbit to another.

In 1924, Pauli introduced the concept of a "new degree of freedom" into quantum mechanics. The following year, G. Uhlenbeck and S. Goodsmith defined it as the spin of an electron.

Pauli proposed the exclusion principle, according to which two identical particles with half-integer spin (their own angular momentum) cannot simultaneously be in the same state. Formulated for electrons in an atom, Pauli's principle was later extended to any particles with half-integer spin (fermions). Electrons have half-integer spin. Pauli's ban did not apply to other particles with integer spin.

According to Pauli's principle, a spin has two possible orientations in a magnetic field: the spin axis can be directed in the same direction as the field, or in the opposite direction. The very motion of an electron along its orbit in an atom determines one more axis, the orientation of which depends on the applied external field. Since there are various combinations of orientations (spin and orbital), this explains the existence of a large number of atomic energy states.

In his subsequent works, Pauli showed that the exclusion principle is a consequence of the connection between the spin and the Fermi - Dirac statistics that exists in relativistic quantum mechanics, and also gave an analytical justification why electrons do not occupy the lowest energy level in an atom. To do this, he had to improve Bohr's model.

The scientist suggested that the orbits of electrons in an atom are described by four quantum numbers for each electron. These numbers are used to determine the basic energy level of an electron, its orbital angular momentum, its magnetic moment and the orientation of its spin. Any of these quantum numbers can take on one of certain values, while only some combinations of these values exist. Based on the Pauli exclusion principle, no two electrons in a system can have the same sets of quantum numbers, and any of the shells of an atom contains the number of orbits determined by the values of the quantum numbers.

The exclusion principle, developed by Pauli, played a major role in understanding the laws governing the structure and behavior of the electron shells of atoms, atomic nuclei, and molecular spectra.

The exclusion principle also underlies the Fermi - Dirac statistics, which played an important role in understanding the physics of the microworld. Thanks to him, the quantum theory of solids was developed, as well as statistics for the electron gas were determined, formed the basis for explaining the thermal, magnetic and electrical properties of solids.

Thanks to Pauli's work, the system of arrangement of elements in the periodic table and their chemical interaction were explained.

Together with Schrödinger, Heisenberg, Bohr and Dirac, Pauli developed the theoretical apparatus used to describe atomic and subatomic systems. After Heisenberg proposed a matrix representation of quantum mechanics in 1926, Pauli used it to describe the observed spectrum of hydrogen.

As a result of the research of these scientists, a quantum mechanical model of the atom was created. Thanks to Pauli's efforts, quantum mechanics has found its application in the fields of science that study the physics of high-energy particles and the interaction of particles with light and other forms of electromagnetic fields. Later, these areas of physics came to be called relativistic quantum electrodynamics.

In 1927, Pauli proposed a generalization of the Schrödinger equation describing particles with half-integer spin and introduced spinors to describe the spin of an electron.

After the scientist took the post of professor at the Federal Polytechnic Institute in Zurich in 1928, the circle of his scientific interests expanded significantly. Pauli became interested in solid state physics, in particular in the problems of dia- and paramagnetism, quantum field theory and the physics of elementary particles.

As a professor at the Zurich Institute, he remained until his death, with the exception of two periods spent by the scientist in the United States of America.

In 1930, Pauli made another brilliant discovery. Numerous studies of beta decay, carried out in the 1930s, led many scientists to the conclusion that the total energy of the neutron decay products - an electron and a proton - is less than the energy of the neutron before decay. This meant that at some moments in the microworld the laws of conservation of energy and momentum are not fulfilled. Pauli strongly opposed this idea. In his letter to the participants in the Tübingen seminar, he suggested that the beta decay products included another unknown particle. Since at that time it was impossible to experimentally prove the existence of a particle, the scientist put forward a hypothesis that it has a weak charge and therefore cannot be registered.

The inability to register the particle explained the loss of energy. By 1933, Pauli had formulated the basic properties of a particle that Enrico Fermi called the neutrino. It was possible to experimentally prove the existence of neutrinos only twenty years later - in 1956.

In 1940, the scientist proved the theorem of the connection between spin and statistics.

Fearing that German troops would invade Switzerland, the scientist accepted an invitation from Princeton University in 1941 and moved to the United States. Until 1946, Pauli worked at Princeton as a professor at the Institute for Fundamental Research, heading the Department of Theoretical Physics.

In 1945, "for the discovery of the exclusion principle, which is also called the Pauli exclusion principle," the scientist was awarded the Nobel Prize in physics. Pauli did not travel to Stockholm for the award ceremony, and it was handed over to him through an employee of the American embassy. The following year, the scientist sent his Nobel lecture "The exclusion principle and quantum mechanics" to Stockholm, in which he summed up his work in the field of quantum mechanics, including the development of the Pauli principle.

In 1946, the Nobel laureate returned to Zurich, where he accepted Swiss citizenship and continued teaching at the Polytechnic Institute in Zurich.

In his last works, the brilliant scientist developed particle physics and conducted research on the interaction of high-energy particles and interaction forces.

Niels Bohr called his young colleague "a clear conscience of physics" because Pauli was ruthless and too critical of both his own work and the work of his colleagues. Even the work of his friends received from him a characterization as "completely wrong" or "not only wrong, but not even reaching the level of error!" During his lifetime, he became the protagonist of many anecdotes. Rumor has it that after Heisenberg presented his new theory to Pauli, he received a letter from Pauli some time later. In the letter was drawn a square marked "I can draw like Titian", and at the bottom of the letter in small handwriting was written: "Only the details are missing."

The famous scientist was one hundred percent theorist. It was rumored that as soon as he entered the research laboratory, the sensitive electronic equipment immediately failed. This "Pauli effect", which also became world famous, was included in various collections from the category of "physicists are joking."

Among the many cases associated with the Pauli effect, there was one. Once in the laboratory of James Frank in Göttingen, an expensive installation was destroyed by an unexpected crushing explosion. As it turned out later, the explosion occurred at the same time when the train in which Pauli was traveling from Zurich to Copenhagen stopped for a few minutes in Göttingen.

The first marriage of the famous scientist was unsuccessful. In 1934 he married again - to Francis Bertram. The couple loved to listen to music, attended the theater.

Pauli's lonely long-distance walks have become the talk of the town. He also enjoyed fishing and hiking in the Alps.

One of the scientist's best friends was the world famous psychologist Carl Gustav Jung, with whom Pauli actively corresponded from 1923 until his death. Their correspondence revealed that the lion's share of Jung's explanation of synchronicity was in fact Pauli's. In addition, the scientist was interested in archetypes, the concept of the collective unconscious, the comparison of the inner world of a person with the outer world, raised in the works of Jung.

In 1918, Mr .. P. entered the University of Munich, where he studied under the guidance of the famous physicist Arnold Sommerfeld. At this time, the German mathematician Felix Klein was busy publishing a mathematical encyclopedia. Klein asked Sommerfeld to write a review of Einstein's general and special relativity, and Sommerfeld, in turn, asked 20-year-old P. to write this article. He quickly wrote a 250-page article, which Sommerfeld described as “simply masterful,” and Einstein praised.

In 1921, after completing his doctoral dissertation on the theory of the hydrogen molecule and receiving his doctorate as soon as possible for the university, P. went to Göttingen, where he took up scientific research with Max Born and James Frank. At the end of 1922 he worked in Copenhagen as an assistant to Niels Bohr. Work under the leadership of Sommerfeld, Born, Frank and Bohr awakened P.'s interest in a new field of physics - quantum theory, which studied the atom and subatomic particles, and he completely immersed himself in the problems facing physicists in this area.

Two more significant shortcomings of Bohr's model helped P. in the future to make a significant contribution to quantum theory. First, this model could not explain some of the subtle details in the hydrogen spectrum. For example, when an atomic gas was placed in a magnetic field, some spectral lines split into several closely spaced lines - an effect first discovered by Peter Zeeman in 1896. More important, however, the stability of the electron orbits was not fully explained. While it was considered obvious that the electrons could not spiral onto the nucleus, continuously emitting radiation, there was no clear reason why they should not descend in jumps, moving from one allowed orbit to another and gathering together in the lowest energy state.

In 1923, Mr .. P. became an assistant professor of theoretical physics at the University of Hamburg. Here, at the beginning of 1925, he was engaged in theoretical studies of the structure of atoms and their behavior in magnetic fields, developing the theory of the Zeeman effect and other types of spectral splitting. He suggested that electrons have a property that Samuel Goudsmit and George Uhlenbeck later called spin, or intrinsic angular momentum. In a magnetic field, the electron spin has two possible orientations: the spin axis can be directed in the same direction as the field, or in the opposite direction. The orbital motion of an electron in an atom defines another axis, which can be oriented in different ways depending on the applied external field. The various possible combinations of spin and orbital orientations are slightly different energetically, which leads to an increase in the number of atomic energy states. Transitions of an electron from each of these sublevels to some other orbit correspond to slightly different wavelengths of light, which explains the fine splitting of spectral lines.

Soon after P. introduced such a property of the "two-valued" electron, he analytically explained why all the electrons in the atom do not occupy the lowest energy level. In Bohr's model, which he improved, the permissible energy states, or orbits, of electrons in an atom are described by four quantum numbers for each electron. These numbers determine the basic energy level of the electron, its orbital angular momentum, its magnetic moment and (this was the contribution of P.) the orientation of its spin. Each of these quantum numbers can take only certain values, moreover, only some combinations of these values are allowed. He formulated a law that became known as the Pauli exclusion principle, according to which no two electrons in a system can have the same set of quantum numbers. So, each shell in an atom can contain only a limited number of electron orbits, determined by the admissible values of quantum numbers.

The Pauli exclusion principle plays a fundamental role in understanding the structure and behavior of atoms, atomic nuclei, the properties of metals and other physical phenomena. He explains the chemical interaction of elements and their previously incomprehensible arrangement in the periodic table. P. himself used the exclusion principle in order to understand the magnetic properties of simple metals and some gases.

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Soon after P. formulated his exclusion principle, quantum theory received a solid theoretical foundation thanks to the works of Erwin Schrödinger, Werner Heisenberg and P.A.M. Dirac. The theoretical apparatus they used to describe atomic and subatomic systems came to be called quantum mechanics. Bohr's atomic model was replaced by a quantum mechanical model, which was more successful in predicting spectra and other atomic phenomena. As for the achievements of P., they made it possible to extend quantum mechanics to areas such as the physics of high-energy particles and the interaction of particles with light and other forms of electromagnetic fields. These areas became known as relativistic quantum electrodynamics.

In 1928, Mr .. P. replaced Peter Debye as professor at the Federal Institute of Technology in Zurich, where he remained until the end of his life, with the exception of two periods spent in the United States; he spent the academic year 1935/36 as a visiting lecturer at the Institute for Basic Research in Princeton, NJ and during World War II, when, fearing that Germany would invade Switzerland, he returned to the same institute where he headed Department of Theoretical Physics from 1940 to 1946

In the 30s. he made another important contribution to physics. Observations of the beta decay of atomic nuclei, in which a neutron in the nucleus emits an electron, turning into a proton, revealed an obvious violation of the energy conservation law: after taking into account all the registered decay products, the energy after decay turned out to be less than its value before decay. In 1930, P. put forward a hypothesis, according to which it was assumed that during such a decay, some unregistered particle (which Enrico Fermi called a neutrino) is emitted, carrying away the lost energy, and while the law of conservation of angular momentum remained in force. Eventually, neutrinos were detected in 1956.

In 1945, Mr .. P. was awarded the Nobel Prize in Physics "for the discovery of the exclusion principle, which is also called the Pauli exclusion principle." He was not present at the award ceremony, and an employee of the American Embassy in Stockholm received it on his behalf. In the Nobel lecture sent to Stockholm the following year, P. summed up his work on the principle of exclusion and quantum mechanics.

P. became a Swiss citizen in 1946. In his further work, he sought to shed light on the problems of interaction of high-energy particles and forces with which they interact, i.e. dealt with the field of physics, which is now called high-energy physics, or particle physics. He also did an in-depth study of the role that symmetry plays in particle physics. Possessing truly fantastic abilities and the ability to penetrate deeply into the essence of physical problems, he was intolerant of vague arguments and superficial judgments. He subjected his own work to such ruthless critique that his publications are virtually free of error. Colleagues called him "the conscience of physics."

After a divorce following a short and unhappy first marriage, P. in 1934 married Francis Bertram. Having a deep interest in philosophy and psychology, he took great pleasure in conversations with his friend K.G. Jung. He also held art, music and theater in high regard. During his holidays he liked to swim, wander through the mountains and forests of Switzerland. P.'s intellectual abilities were in sharp dissonance with his "ability" to work with his hands. His colleagues used to joke about the mysterious Pauli effect, when the mere presence of a short and plump scientist in the laboratory seemed to cause all sorts of breakdowns and accidents. In early December 1958, P. fell ill and soon, on December 15, died.

In addition to the Nobel Prize, P. was awarded the Franklin Franklin Institute Medal (1952) and the Max Planck Medal of the German Physical Society (1958). He was a member of the Swiss Physical Society, the American Physical Society, the American Association for the Basic Sciences, and a foreign member of the Royal Society of London.