A NOTE ON QUATERNION ALGEBRA AND FINITE ROTATIONS

In this paper after briefly recollecting the main properties of Hamilt on's quaternion field, the deep interrelations between the group of se cond-order orthogonal Cartesian tensors and the quaternionic product i s emphasized. The topic discussed plays an important role in dealing w ith questions about the kinematies of deformable bodies when Lagrangia n measures for finite deformations are assumed and Cauchy's polar-deco mposition theorem is applied.