Congratulations to Igor Viktorovich Puzynin! On 24 April 2023, Igor Viktorovich Puzynin, Advisor to the Directorate of the Meshcheryakov Laboratory of Information Technologies of the Joint Institute for Nuclear Research, Doctor of Physical and Mathematical Sciences, Professor, Honored Scientist of the Russian Federation, celebrates his 85th birthday. After graduating from the Faculty of Mechanics and Mathematics of Moscow State University in 1960, I.V. Puzynin was assigned to the Laboratory of Theoretical Physics at JINR. All scientific activity of Igor Viktorovich, lasting more than 60 years, is inextricably bound with JINR, where he went from a senior laboratory assistant with a higher education to the director of the Laboratory of Information Technologies. Igor Viktorovich Puzynin is a well-known scientist in the field of computational and applied mathematics. Under his leadership, a scientific direction on the creation, theoretical justification and practical implementation of computational physics methods for the numerical study of nonlinear multi-parameter models of complex physical systems was developed at JINR. The uppermost contribution to the development of this scientific direction is the elaboration of a unified approach for the numerical analysis of boundary and spectral problems for systems of nonlinear multi-parameter differential and integro-differential equations based on the generalization of the continuous analogue of Newton's method. Thanks to the development of this approach, a number of important physics results were obtained in the theory of muon catalysis, nuclear theory, nonlinear problems of quantum chromodynamics and condensed matter physics. I.V. Puzynin headed the work on mathematical and software support of theoretical calculations under the Research Program on the Phenomenon of Muon Catalysis, approved by a joint decision of the USSR State Committee for the Use of Atomic Energy and the Presidium of the USSR Academy of Sciences. He was the co-leader of the Institute-wide theme "Theoretical and experimental studies of the electronuclear method for generating energy and transmuting radioactive waste”. At present, he leads the development of mathematical models and methods, algorithms and programs for the numerical study of processes that emerge when materials are irradiated with particle beams. Working as Deputy Director and then as (the first) Director of the Laboratory of Information Technologies, I.V. Puzynin made a great contribution to bringing together the scientific interests of theoretical physicists and experimenters from different JINR Laboratories with specialists in numerical analysis and the computer processing of experimental information, to updating and modernizing the JINR computer and network infrastructure and enhancing the professional level of network support specialists. Professor I.V. Puzynin made a great contribution to training young scientists. In 1968–1980, he worked at the Department of Theoretical Nuclear Physics of the Faculty of Physics of Moscow State University, since 1991 he has been a professor at the Faculty of Mathematics of Tver State University. For many years, Igor Viktorovich has been a member and a deputy chairman of the MLIT Dissertation Council. Under his supervision, 8 doctoral and 11 Ph.D. theses were defended, two of his students became academicians of the Mongolian Academy of Sciences. I.V. Puzynin is the author of more than 300 scientific publications. He is Honorary Professor of Tver State University, Honorary Doctor of Plovdiv University (Bulgaria) and Honorary Professor of the Mongolian State University. Igor Viktorovich Puzynin was awarded the Medal of the Order “For Merit to the Fatherland”, II degree, the medals “Veteran of Labor” and “In Commemoration of the 850th Anniversary of Moscow”, the departmental badge of distinction in labor “Veteran of Nuclear Energy and Industry”, Certificates of Honor of the Ministry of Education and Science of the Russian Federation, of JINR and Dubna, JINR’s Honorary Diploma, has the honorary title of “Honored Worker of Science of the Russian Federation”, the title of “Honorary Fellow of JINR”. He received the medal “50 Years of Poland's Participation in JINR”, the Gold Medal of the Technical University of Košice (Slovakia), the medal “Friendship” (Mongolia). In 2021, by a decree of the President of Mongolia, I.V. Puzynin was awarded the Order of the Polar Star. For more than sixty years, Igor Viktorovich has been going hand in hand with his wife Taisiya Petrovna, a devoted friend and a co-author of a multitude of joint scientific publications. Together they raised two wonderful sons and now enjoy their grandchildren. Dear Igor Viktorovich! We sincerely congratulate you on your anniversary and wish you good health, energy and success in your work, well-being, mutual understanding and happiness in family life. May your loved ones delight you with their love, may the sun warm you with its warmth on this spring day, may your optimism and your inherent sense of humor not dry up. All the very best to you! Directorate of the Meshcheryakov Laboratory of Information Technologies, JINR Directorate, colleagues and friends
