In 1948, the research group of Academician I.E. Tamm on the development of thermonuclear weapons was included Andrei Dmitrievich Sakharov. For many years of his scientific biography, he was the author and co-author of some key discoveries in the field of physics.
Candidate dissertation A.D. Sakharov, which he defended in 1947, was devoted to the problem of nonradiative nuclear transitions. He proposed a new selection rule for charging parity. In addition, he found a way to take into account the interaction of an electron and a positron in the production of pairs. As a result of work on the dissertation, the scientist made an important discovery. The difference in the energies of the two levels of the hydrogen atom is small because in the free and bound state, the electron interacts with its own field in different ways. Earlier, similar assumptions were made by the American astrophysicist H. Bethe, who was awarded the Nobel Prize for this discovery in 1967. The calculations of the Russian scientist were kept secret for a long time. But it was thanks to them that in 1948 Sakharov was invited to Tamm's group.
Academician I.E. Tamm gathered scientists to test the hydrogen bomb project. The project was proposed by Ya.B. Zeldovich. Sakharov's activities in a group of scientists turned out to be fruitful. The assumptions put forward by him were confirmed by directing the research in the right direction. He also made constructive changes. Andrey Dmitrievich's contribution to the work on the creation of the bomb was very great. He was later called "the father of the thermonuclear bomb." The group's work was successfully completed in August 1953.
Scientific activity of A.D. Sakharova is not limited to work on the creation of a hydrogen bomb. In 1950, Sakharov and Tamm put forward the idea of magnetic plasma confinement. Calculations of installations for controlled thermonuclear fusion were carried out. Sakharov was the first to propose the idea of magnetic isolation of a deuterium-tritium plasma heated to a million degrees. In 1951, in the work "Theory of a magnetic thermonuclear reactor", the design of the so-called "magnetic trap" was outlined. The scientist suggested that at the maximum temperature of the plasma, equally charged nuclei would be able to approach each other. As a result of such a synthesis, a large amount of energy should be released. Installation for magnetic plasma confinement is called "Tokamak". For more than 60 years, physicists from many countries of the world have been trying to achieve a positive energy balance based on the scientific developments of A.D. Sakharov.
Also A.D. Sakharov came up with the idea of creating superstrong magnetic fields. They were asked to do this by compressing the magnetic flux with a conductive cylindrical shell. In 1961, scientists put forward the idea of using laser compression to obtain a controlled thermonuclear reaction. All this constituted the modern basis for serious research in the field of thermonuclear energy.
Explaining the baryon asymmetry of the Universe is another major achievement of the scientist. For a long time, it was believed that particles and antiparticles are absolutely identical. HELL. Sakharov investigated the question of the reason for the absence of antigalaxies and anti-stars. On this basis, in 1967, he formed the conditions for the emergence of asymmetry in the first moments of the appearance of the hot Universe. CP-parity violation in the processes of scattering of elementary particles was named as one of the reasons. Another reason was the violation of symmetry in time reversal. As a result of analyzing the reasons for the instability of the proton, Sakharov proposed a conclusion about the nonconservation of the baryon charge.
Academician Sakharov's field of scientific interest was also the problem of the inhomogeneity of the distribution of matter in the Universe. At the stage of the creation of the Universe, all substances were homogeneous in composition.As a result of changes in concentration in one place, there was an accumulation of the surrounding matter falling on this center of attraction. In 1963, the work "The initial stage of the expansion of the Universe and the emergence of inhomogeneity in the distribution of matter" was devoted to this issue. In it A.D. Sakharov was the first to suggest that quantum fluctuations are the cause of pregalactic inhomogeneities. In 2011, based on these studies, astrophysicists discovered inhomogeneities in the relict cosmic background. In honor of the scientist who first put forward this idea, they are named "Sakharov's oscillations".