# Проф. Петър Петров Райчев

Professor Peter Raychev was an eminent scientist with a bright presence in the field of Theoretical Nuclear Physics. A man of insight, he had the talent of generating original ideas, of finding and solving problems, of exploring new directions and avenues of research and attracting the interest of many other scientists. Peter Raychev is one of the founders of the Group Theoretical approach in the structure of atomic nuclei. He proposed and developed, together with his younger collaborators, several advanced nuclear structure models based on the concept of the interacting vector bosons and on the formalism of q-deformed algebras and groups. His work in the field of the group theoretical methods has had a strong impact on the international Nuclear Physics community, inspiring new ideas and agendas for further research in theoretical studies. His name will be always present in the nuclear physical science.

Professor Peter Petrov Raychev was born on May 20, 1938 in Plovdiv (Bulgaria). He graduated from the "St. Kliment Ohridsky" University of Sofia i n 1961. From 1961 till 1969 P. Raychev was an assistant professor at the Physics Department of the University of Sofia. From 1970 till 1972 he was a r esearch a ssociate at the Laboratory of Theoretical Physics of the Joint Institute for Nuclear Research in Dubna (Russia). There he prepared his PhD thesis entitled "On the Algebraic Methods for the Description of the Deformed Even- Even Nuclei", defended in 1973. From 1973 till his death in 2004 Peter Raychev had the position of senior researcher at the Institute of Nuclear Research and Nuclear Energy of the Bulgarian Academy of Sciences in Sofia, Bulgaria. In 1991 he defended his Dr. SC. thesis on the topic "Group Theoretical Methods in Nuclear Theory". In 1992 he became a full professor in Nuclear Physics.

Professor P. Raychev has published more than 100 papers in the field of nuclear, molecular and theoretical physics. Most of them appeared in advanced journals, such as Physics Letters, Physical Review, Journal of Physics, and others. They are widely cited in many international journals and books. He is also the author of a university text-book in Atomic Physics (in two volumes, published in 1965) and 14 books, the most important amongst them being "Elementary Introduction to Quantum Physics" Sofia, Technica, 1968; "Physics of the Atomic Systems", Sofia, Nauka i Iskustvo, 1980 (of which a new version –finished a month before his death - is to appear soon) and "The Heart of the Atom", Sofia, LODOS, 2002. He has also published more than 150 articles popularizing the problems of Nuclear and Elementary Particle Physics and Cosmology. Prof. P. Raychev established and developed active col l aboration with leading nuclear physicists as Prof. G. Afanasiev, Prof. V. Vanagas , Prof. Yu. F. Smirnov, Prof. D. Bonatsos, Prof. A. Faessler, Prof. N. Lo Iudiche, Prof. W. Scheid and others, providing important results in the field of nuclear theory.

Professor Raychev was a supervisor of four PhD students and more than 10 graduate students in Nuclear and Theoretical Physics. Working with Prof. P. Raychev was an exciting experience: new ideas were created after long hours of heated and interesting discussions. Alongside tuition in physics, he gave his students and young collaborators knowledge about many interesting facts in the field of history and literature, the world of jazz and the cinema and the life of famous people. His lectures on Atomic Physics, Group Theoretical Methods in Quantum Mechanics, Classical and Quantum Mechanics, Algebraic Methods in Nuclear Theory, Atomic and Nuclear Physics given at Sofia University, and the lectures on Foundations of Modern Physics given at the New Bulgarian University, will be remembered by many people.