Please note that the content of this book primarily consists of articles available from Wikipedia or other free sources online. Prof. dr. Jan opusza ski (October 21, 1923-April 30, 2008) was a Polish theoretical physicist and author of several textbooks about classical, statistical and quantum physics. In the field of quantum field theory, he is most famous as co-author of the Haag-Lopuszanski-Sohnius theorem concerning the possibility of supersymmetry in renormalizable QFT's. Jan opusza ski was born October 21, 1923 in Lwów, Poland. During 1945-50 he studied physics at the University of Wroc aw. In 1950, he received his M.A. in Wroc aw, in 1955 his Ph. D. at the Jagiellonian University in Cracow. Since 1947 he was part of regular staff member at the University of Wroc aw, in 1968 he became full professor.