A century ago, Dirac proposed his equation merging quantum mechanics with special relativity. During the last century, the Dirac equation played the key role for the predictions of antimatter, electron spin, spin magnetic moments of elementary spin-1/2 fermions, fine structure, quantum dynamics of charged particles in electromagnetic fields, and so on. Whereas long-standing fundamental problems are remained, such as finding relativistic spin operators of massive particles and the corresponding position operators. In this talk, I will briefly introduce a history about the beginning of relativistic quantum mechanics, present the rigorous derivation of spin operators and the corresponding position operator, and discuss the fundamental properties of spin and position operators.
Sam Young CHO is a professor of physics at Chongqing University, China. He received his Ph D from POSTECH, Korea. He worked as a Postdoctoral fellow under the Brain Korea 21 at Yensei University, Korea. He has got UQ postdoctoral research and APD (Austrailian Postdoctoral Research) fellowships and worked in the University of Queensland, Austrailia. His research area is theoretical condensed matter physics including quantum (spin) transport in mesoscopic systems, quantum gate operations in supercoducting qubit systems, and quantum entanglement and correlation in quantum phase transition systems.