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Lev Davidovich Landau

Data de nastere:

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Data mortii:

Locul mortii:

22 Jan 1908

Baku, Azerbaijan, Russian Empire

1 April 1968

Moscow, USSR

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Lev Landau's mother had trained in medicine and she had undertaken work in physiology, while his father was a petroleum engineer who worked at the oil fields in Baku on the Caspian Sea. Lev was a prodigy in mathematics when he was a child. In fact his achievements at school were such that by the age of thirteen he had completed his secondary schooling and had the qualifications to enter university. His parents did not like the idea that he should begin his university studies a such a young age, and this was almost certainly a wise decision on their part. Lev was sent to Baku Economic Technical School for a year to delay his entry to university studies.

Landau was still only fourteen years old when he entered Baku University (later called the Kirov Azerbaijan State University) in 1922 and by this time he was already enthusiastic about mathematics, physics and chemistry. There he studied physics in the department of Mathematics and Physics but he also studied chemistry and, although he did not carry his studies of this topic any further through his university education, it remained one of his life-long interests. In 1924, after two years at Baku University, he moved to the Leningrad State University, graduating in 1927. In fact his first publication appeared in print in the year he graduated, being a paper on quantum theory. He continued research at the Leningrad Physico- Technical Institute.

In 1929 Landau set off on eighteen months foreign travel, visiting Germany, Switzerland, Holland, England, Belgium, and Denmark. The visits which were most valuable to his research were those to Göttingen, Leipzig and particularly to Copenhagen where he worked in Niels Bohr 's Institute for Theoretical Physics :

His participation in Bohr's seminar played an important role in Landau's development as a theoretical physicist.

From that time on he considered himself a pupil of Bohr and it was Bohr's influence that dictated the direction of Landau's future work. The visit to Copenhagen also seemed to mark a change in Landau's character :

Landau, then and for some years afterwards, was an extremely provocative young man, who liked to shock.

In 1932, soon after he returned to Leningrad, Landau was appointed as head of the Theory Division of the Ukrainian Technical Institute in Kharkov and he was also appointed to the chair of theoretical physics at the Kharkov Institute of Mechanical Engineering. He moved to Kharkov to take up these posts, receiving a doctorate in Physical and Mathematical Sciences in 1934. One of his first projects in Kharkov was to organise an international conference on theoretical physics, and Niels Bohr attended the meeting :

Landau presided; Bohr opened the discussions on all papers ...

Soon afterward Landau was back in Copenhagen at a conference organised by Bohr :

... wearing a red coat and still provocative. During the next two years he produced original scientific papers at an average rate of one every six weeks and covered an astonishing range of subjects.

This extraordinary productivity was soon rewarded for, in addition to his other positions, in 1935 he received the title of professor and was made head of Physics at the Kharkov Gorky State University. Landau soon made his School in Kharkov the centre of theoretical physics in the USSR.

In 1937 Landau went to Moscow to become Head of the Theory Division of the Physical Institute of the USSR Academy of Sciences . He worked on atomic collisions, astrophysics, low-temperature physics, atomic and nuclear physics, thermodynamics, quantum electrodynamics, kinetic theory of gases, quantum field theory, and plasma physics. The work he did on the theory to explain why liquid helium was super-fluid earned him the 1962 Nobel Prize for Physics.

Perhaps some details of the strange behaviour of liquid helium at a temperature just above absolute zero would be useful. It had been noted experimentally that if liquid helium at these low temperatures was placed in a beaker, then it climbed out of the beaker until the level outside was equal to that inside. Similarly liquid helium would climb into the beaker if the level outside exceeded that in the beaker. Landau devised a theory to explain such behaviour which was published in 1941. It predicted a new phenomenon, namely a temperature wave described a "second sound", and three years later experimental evidence produced in Moscow confirmed the existence of "second sound".

In 1938, Landau was imprisoned for a year as a suspected German spy. He wrote:

I spent a year in prison and it was clear that I would be unable to live for even another half year.

Russian scientists tried to force the authorities to release him, with the leading physicist Peter Kapitza claiming he would stop his scientific work unless Landau was released. Kapitsa and Niels Bohr both wrote letters to Stalin insisting that Landau must be released. He was released in 1939 and reinstated as a research fellow at the Institute of Physical Problems.

Another major contribution made by Landau was the writing of a number of outstanding textbooks and research monographs. These include Statistical physics (1938), Mechanics, Field theory, Quantum mechanics, and Theory of elasticity. His most famous book, however, is his ten volume Course of Theoretical Physics written jointly with E M Lifshitz who was Landau's research student. They began work on this in the 1930's and the first part of the book is based on lecture notes. Lifshitz continued to work on the book after Landau's death and it was not completed until 1979. The work includes many of the results of Landau and Lifshitz 's research over many years including the results of many jointly written research papers.

The chapters of the book indicates the main topics of their joint research: Mechanics, theory of fields, quantum mechanics, quantum electrodynamics, classical statistical physics, quantum statistical physics, fluid mechanics, theory of elasticity, electrodynamics of continuous media, and physical kinetics.

In 1962, Landau was involved in a car accident after which he was unconscious for six weeks :

... his injuries included 11 broken bones and a fractured skull.

Several times doctors declared him clinically dead. Remarkably Landau regained consciousness and although in most ways he returned to normal, he could never again perform creative work. He died six years after his accident having never completely recovered.

We have given some quotes above concerning Landau's character. Further remarks are given in :

His personal qualities are something of an enigma. He had a flaming sincerity for - and about - science. He attracted students by his enthusiasm and evident knowledge, but to a greater age than most retained aspects of the enfant terrible. He could also be hot and merciless in criticism. Yet those who knew him, from Niels Bohr to the writer of a Soviet appreciation of his 50th birthday, agreed that there was human warmth below his sharpness.

Landau received many international honours for his contributions. He was elected to the Royal Danish Academy of Sciences (1951), The Netherlands Academy (1956), The British Physical Society (1959) and the Royal Society of London (1960). Also in 1960 he was elected to the U.S. National Academy of Sciences and the American Academy of Arts and Sciences . In addition to the Nobel Prize in 1962, he received the Fritz London Prize in 1960 and, in the same year, the Max Planck Medal.

Source:School of Mathematics and Statistics University of St Andrews, Scotland