Lev Landau: short biography, contribution to science

Lev Landau (years of life - 1908-1968) is a great Soviet physicist, native of Baku. He owns a lot of interesting research and discoveries. Can you answer the question, Lev Landau for which he received the Nobel Prize? In this article we will talk about his achievements and the main facts of the biography.

The Origin of Lev Landau

You can talk for a long time about such a scientist as Lev Landau. Years of life, occupation and achievements of this physicist - all this is probably of interest to readers. Let's start from the very beginning - with the origin of the future scientist.

He was born in the family of Lubov and David Landau. His father was a rather famous oil engineer. He worked in oil fields. As for the mother, by profession she was a doctor. It is known that this woman carried out physiological studies. Apparently, Lev Landau was a descendant of an intelligent family. His older sister, by the way, became a chemical engineer.

years of education

Lev Davidovich studied in high school, which he graduated brilliantly at the age of 13. His parents felt that their son was still very young for studying at a higher educational institution. Therefore, they decided to send him for one year to the Baku Economic Technical School. Then, in 1922, he was admitted to Baku University. Here Lev Landau studied chemistry and physics. Two years later Lev Davidovich transferred to the Leningrad University, to the Physics Department.

The first scientific work, postgraduate study

At the age of nineteen, Landau became the author of four scientific papers that were published. In one of these works the so-called density matrix was first used. This term is widely used today. He describes quantum energy states. Landau graduated from the university in 1927. Then he entered the graduate school, choosing the Leningrad Institute of Physics and Technology. In this educational institution he worked on quantum electrodynamics and magnetic theory of electron.

Business trip

Between 1929 and 1931, Lev Landau was on a scientific mission. The years of life, occupation and achievements of this scientist are associated with close cooperation with foreign colleagues. So, during the trip he traveled to Switzerland, Germany, the Netherlands, England and Denmark. During these years he met and became acquainted with the founders of quantum mechanics, which then just appeared. Among the scientists with whom Landau met, were Wolfgang Pauli, Werner Heisenberg and Niels Bohr. To the last Lev Davidovich has kept friendly feelings for all his life. This scientist especially strongly influenced Landau.

Lev Davidovich, while abroad, carried out important studies of free electrons (their magnetic properties). In addition, together with Peierls, he also carried out research on relativistic quantum mechanics. Thanks to these works, Lev Landau, whose occupation interested foreign colleagues, began to be considered one of the leading theoretical physicists. The scientist learned how to handle very complex theoretical systems. It should be noted that later this skill was very useful to him, when Landau began to conduct research on low-temperature physics.

Moving to Kharkov

Lev Davidovich returned to Leningrad in 1931. However, soon he decided to move to Kharkov, which at that time was the capital of Ukraine. Here the scientist worked at the Ukrainian Physicotechnical Institute, was the head of his theoretical department. Simultaneously, Lev Davidovich was head of the Department of Theoretical Physics at Kharkov University and Kharkov Institute of Engineering and Mechanics. In 1934, the USSR Academy of Sciences awarded him the degree of Doctor of Physical and Mathematical Sciences. For this, Landau did not even need to defend his thesis. The title of professor was awarded already next year to such a scientist as Lev Landau.

His occupation covered more and more areas of science. Landau in Kharkov published works on such topics as the dispersion of sound, the origin of the energy of stars, the scattering of light, energy transfer occurring in collisions, superconductivity, the magnetic properties of various materials, etc. Thanks to this, he became known as a theorist with unusually versatile scientific interests.

A distinctive feature of Landau's works

Subsequently, when plasma physics appeared , Landau's papers on particles interacting electrically turned out to be very useful. Having borrowed some concepts from thermodynamics, the scientist expressed a number of innovative ideas concerning low-temperature systems. It must be said that all the works of Landau are characterized by one important feature - the virtuoso use of the mathematical apparatus in the search for solving complex problems. Lev Landau made a significant contribution to the quantum theory, as well as to research on the interaction and nature of elementary particles.

Leo Landau School

The range of his research is truly wide. They cover practically all the main areas of theoretical physics. Owing to such breadth of his interests, the scientist attracted to Kharkov a lot of talented young scientists and gifted students. Among them was Lifshits Evgeny Mikhailovich, who became an employee of Lev Davidovich and his closest friend. The school, which grew up around Lev Landau, turned Kharkov into one of the leading centers of theoretical physics in the USSR.

The scientist was convinced that the theoretical physicist should be thoroughly grounded in all areas of this science. To this end, Lev Davidovich developed a very rigorous training program. He called this program a "theoretical minimum." Applicants who wanted to participate in the seminar, led by him, had to meet very high standards. Suffice it to say that in 30 years, in spite of a lot of people, only 40 people passed exams on the "theoretical minimum". However, those who succeeded in this, Lev Davidovich generously paid his attention and time. In addition, they were given complete freedom of choice when choosing the topic of research.

Creating a course in theoretical physics

Landau Lev Davidovich maintained friendly relations with his colleagues and students. They affectionately called the scholar Dau. To help them in 1935, Lev Davidovich created a detailed course in theoretical physics. It was published by Landau in conjunction with EM Lifshitz and was a series of textbooks. Their content was updated and revised by the authors over the next 20 years. Huge popularity of these benefits. They were translated into many languages of the world. At present, these textbooks are rightly considered to be classical. In 1962, for the creation of this course, Landau and Lifshitz received the Lenin Prize.

Working with Kapitza

Lev Davidovich in 1937 responded to the invitation of Peter Kapitsa (photo is presented below) and became head of the theoretical physics department at the Moscow Institute of Physical Problems, newly created at the time. However, the scientist was arrested the following year. A false accusation said that he was engaged in espionage in favor of Germany. Only thanks to the intervention of Kapitza, who personally appealed to the Kremlin, Lev Landau was released.

When Landau moved from Kharkov to Moscow, Kapitsa was engaged in experiments with liquid helium. If the temperature falls below 4.2 K (the absolute temperature is measured in degrees Kelvin and counts from -273.18 ° C, that is, from absolute zero), the gaseous helium becomes a liquid. In this state it is called helium-1. If the temperature is lowered to 2.17 K, it passes into a liquid called helium-2. It has very interesting properties. Helium-2 is able to easily flow through the smallest holes. It seems as if the viscosity is completely absent. The substance rises up the wall of the vessel, as if the force of gravity does not affect it. In addition, its thermal conductivity exceeds the thermal conductivity of copper by hundreds of times. Kapitsa decided to call the superfluid liquid helium-2. However, the test revealed that its viscosity is not zero.

Scientists have suggested that such unusual behavior is due to effects that relate to the field of non-classical physics, and quantum theory. These effects occur only at low temperatures. Usually they make themselves felt in solids, because under these conditions most substances freeze. An exception is helium. This substance remains liquid until absolute zero, if it is not subject to high pressure. Laszlo Tissa in 1938 suggested that in reality liquid helium is a mixture of two forms: helium-2 (liquid superfluid) and helium-1 (liquid normal). When the temperature drops to almost absolute zero, the former becomes the dominant component. This hypothesis explains the appearance of different viscosities under different conditions.

How did Landau explain the phenomenon of superfluidity

Lev Landau, whose brief biography describes only his main achievements, was able to explain the phenomenon of superfluidity, using a completely new mathematical apparatus. Other scientists relied on quantum mechanics, which was used to analyze the behavior of individual atoms. Landau also considered quantum states of a liquid in much the same way as if it were a solid. He put forward the hypothesis that there are two components of excitation, or motion. The first of these is phonons, which describe the normal rectilinear propagation of sound waves for small values of energy and momentum. The second is the rotons, which describe the rotational motion. The latter is a more complex manifestation of excitations, arising at higher values of energy and momentum. The scientist noted that the observed phenomena can be explained by the contributions of rotons and phonons and their interaction.

Landau claimed that liquid helium can be regarded as a "normal" component, which is immersed in a superfluid "background". How can we explain that liquid helium flows through a narrow gap? The scientist noted that only the superfluid component in this case flows. And rotons and phonons collide with the walls that hold them.

The significance of the Landau theory

The Landau theory, as well as its further improvements, played a very important role in science. They not only explained the observed phenomena, but also predicted some others. One example is the propagation of two waves that have different properties and are called the first and second sound. The first sound is ordinary sound waves, while the second is a temperature wave. Thanks to the theory created by Landau, scientists were able to make significant progress in understanding the nature of superconductivity.

Years of the Second World War and Postwar Time

Lev Davidovich was studying explosions and burning during the Second World War. In particular he was interested in shock waves. After May 1945 and until 1962, the scientist worked on various tasks. In particular, he investigated a rare isotope of helium, which has an atomic mass of 3 (usually its mass is 4). Lev Davidovich predicted the existence of a new type of wave propagation for this isotope. "Zero sound" - that's what Lev Davidovich Landau called it. His biography is noted, in addition, participation in the creation of an atomic bomb in the USSR.

Car crash, Nobel Prize and last years of life

At the age of 53 he got into a car accident, which resulted in serious injuries. Many doctors from the USSR, France, Canada, Czechoslovakia fought for the life of the scientist. He remained unconscious for 6 weeks. Within three months after the car crash did not even recognize the loved ones Lev Landau. The Nobel Prize was awarded to him in 1962. However, because of his health condition, he could not go to Stockholm, in order to get it. In the photo below you can see L. Landau and his wife in the hospital.

The prize was awarded to a scientist in Moscow. After that, Lev Davidovich lived for another 6 years, but he could not return to research. Lev Landau died in Moscow as a result of complications from his injuries.

The Landau family

The scientist in 1937 married Drobantseva Concordia, an engineer-technologist in the food industry. This woman was from Kharkov. Years of her life - 1908-1984. A son was born in the family, who later became an experimental physicist and worked at the Institute of Physical Problems. The photo below shows L. Landau and his son.

This is all that can be told about such a scientist as Lev Landau. His biography, of course, includes only basic facts. The theories he created are quite complex for the unprepared reader. Therefore, the article only briefly tells about what made Lev Landau famous. The biography and achievements of this scientist still cause great interest throughout the world.