From 1932 to 1937 the theoretical department in UFTI was headed by L.D.Landau, who laid down in Kharkov the foundations of his school of theoretical physics becoming world famous. After Landau’s leaving for Moscow the theoretical department was headed by his disciple A.I. Akhiezer, and in 1941 another theoretical department was created at UFTI under the guidance of I.M. Lifshitz. After Lifshitz’s moving to Moscow in 1968 this department was in turn headed by A.M.Kosevich, Ye.V.Inopin, A.S.Bakai.

Ivan V. Obreimov

Dmitry D. Ivanenko

Lev D. Landau

Alexander I. Akhiezer

Ilya M. Lifshitz

When in the early 1990s in a difficult economic situation the KIPT had to be reorganized, A.I. Akhiezer was an ardent supporter of a separate institute for theoretical physics, being a constituent of a newly created National Science Center KIPT. By this time his department was headed by his disciple S.V. Peletminsky. Alexander Ill’ich Akhiezer did everything possible for formation of the Institute for Theoretical Physics and to subordinate the National Science Center KIPT to the National Academy of Sciences of Ukraine. In 1996 the part of his plan was realized and the Institute for Theoretical Physics was established. The NSC KIPT was affiliated with the National Academy of Sciences of Ukraine in 2004, already after the death of A.I. Akhiezer.

In 2003 a decree of the Ukrainian Cabinet gave the name of academician of the National Academy of Sciences A.I. Akhiezer to the Institute for Theoretical Physics of NSC KIPT.

The concept of supersymmetry was offered, on the basis of which the representation of spin 1/2 Goldstone fermions was introduced and, for the first time, the basic concepts of the supergravitation theory were formulated. The idea of supersymmetry has allowed to eliminate a number of basic difficulties of the quantum field theory and has provided one of central ideas of constructing a unified theory of fundamental interactions, including gravitation. Various aspects of supersymmetry, supergravitation, superstrings were developed; the mathematical apparatus of the supersymmetry theory and its applications in the elementary particle physics were elaborated.

The theory of polarisation effects was developed for processes of high-energy interaction of photons and electrons with nucleons and light nuclei on the basis of general principles of relativistic invariance and the fundamental properties of the symmetry of interactions. Manifestations of dibaryon resonances in electromagnetic interactions of photons and electrons with light nuclei were investigated. The theory of polarization phenomena at pseudoscalar and vector mesons production in nucleon-nucleon scattering was developed.

Theoretical seminar, 1986. At the blackboard - A.I.Akhiezer.

Theoretical seminar, 2003.

The cross-section and spin observed values for an elastic proton-nuclear scattering at intermediate energies taking into account virtual excitation of target nuclei were obtained on the basis of generalization of the Glauber-Sitenko multiple diffractive scattering theory. The asymptotically uniform solutions in the problem of diffractive hadron-nuclear and nuclear-nuclear scattering in a semitransmittant nuclear model were obtained. Relativistic and unitary model was suggested to study pion-nucleon scattering, photoproduction of pions on the nucleon and Compton scattering on the nucleons.

The possibility of the dynamic chaos phenomenon related to collective excitations of nuclei was predicted. Manifestations of dynamic chaos in nuclei, determining some special features of nuclear interaction, are also studied. The possibility of an anomalous chaos-regularity transition for simple Hamilton systems in periodical external fields was predicted.

A quasiclassical theory of coherent scattering and radiation of high-energy charged particles in oriented crystals was advanced. A dynamic chaos phenomenon for fast particle movement in crystal lattice was predicted. A possibility of an anomalous diffusion for relativistic particle channeling in crystals was shown. A new mechanism of particle beam bending at ultra-high-energy, using bent crystals and nanotubes, based on the process of multiple scattering of particles on atomic rows was offered. The effects of suppression of the bremsstrahlung and coherent radiation of ultra relativistic electrons in thin layers of amorphous and crystalline matter were predicted. A possibility of similar effect for collisions of short bunches of relativistic particles was predicted. A theory of the relativistic electron transition radiation at ultra large radiation formation lengths (up to several hundreds meters) was developed.

In the field of statistical physics, a problem of nonequilibrum entropy determination definition of interacting particles was solved; the microscopic theory of irreversible processes in condensed systems with a spontaneously broken symmetry was advanced. The fermi-liquid approach to superfluid liquids was developed, with the application in the study of equilibrium and kinetic properties of superconductors. The reduced description method of macroscopic nonequilibrium fluctuations was developed. Kinetic and hydrodynamic theories of long-wavelength fluctuations were constructed in microscopic approach on the basis of this method. A stochastic approach for the derivation of general equations of macroscopic fluctuation evolution was elaborated. A number of applications of these approaches in the turbulence theory, in "the long hydrodynamic tails" theory, and the quasilinear theory of plasma were examined.

The microscopic theory of glass formation at melt cooling was constructed, and the vitrification criterion was obtained. The glasses are shown to be generally polycluster structures. A description of thermodynamic, kinetic and mechanical properties of polycluster amorphous solids, in particular, metal glasses, was given. On the basis of the fermi-liquid model a theory of magnetic properties of conducting ferro- and antiferro-magnetic materials, including structurally disordered materials, was constructed.

A theory of diffusive decomposition of multicomponent solid solutions was developed. Since then the theory has found extensive application in materials science and physics of condensed media. A theory of phase transformations in highly nonequilibrum solid solutions, in viscous liquids and melts was constructed. A theory of solute segregation at grain boundaries of polycrystals was proposed. The theory was generalized for solute segregation in materials under irradiation.

Theoretical models were developed to describe the evolution of binary alloys under irradiation; the technique was elaborated for constructing structure-phase diagrams at ordering (disordering) of alloys under irradiation, including radiation-induced cascade formation. For a number of alloys the structure-phase diagrams being the analogues of the equilibrium diagrams were constructed. They determine the equilibrium of different structure-phase states in relation to temperature, irradiation dose and the alloy composition.