The theory of screws: A new geometric representation for the group SU(1,1)

Abstract

Hamilton’s theory of turns, which gives a geometrical description of the elements and structure of the compact group SU(2), is generalized to a theory of screws for the noncompact group SU(1,1). Group elements are pictured as geometric objects in a three-dimensional Minkowski space, and the composition law is reduced to a geometric operation on them. A new classification of elements of SU(1,1), leading to an interesting structural result about the group manifold, is introduced.