From the Complete Yang Model to Snyder's Model, de Sitter Special Relativity and Their Duality

By means of the Dirac procedure, we re-examine Yang's quantized space--time model, its relation to Snyder's model, the dS special relativity and their UV--IR duality. Starting from a dimensionless dS₅-space in a (5+1)-dimensional Mink-space a complete Yang model at both classical and quantum level can be presented and there really exists Snyder's model, the dS special relativity and the duality.