9309902 Yuan Research in theoretical elementary particle physics will include two areas of vital importance in understanding the basic interactions. The first concerns the origins of masses of the fundamental particles. The second concerns the interactions of the heaviest of these particles. Phenomenological implications of various scenarios relevant to these two questions are clarified. The research is important for experiments at existing facilities, and those planned for upcoming facilities. It is crucial for testing our understanding of the forces that exist among elementary particles. ***
