Contractions and expansions of Lie groups and the algebraic approach to scattering

Abstract
A recently introduced algebraic approach to scattering is recast in the language of group contractions and expansions. The expansion describes the deformation of the physical states from one kind of symmetry to another and allows the algebraic derivation of an S matrix. The method is illustrated for scattering models in n-dimensional space of the type SO(n,1) and SO(n,m) with m≥2.