RELATIVISTIC AND NEWTONIAN KAPPA-SPACE-TIMES

The deformations of the Galilei algebra and their associated noncommut ative Newtonian space-times are investigated. This is done by analyzin g the possible nonrelativistic limits of an eleven generator (pseudo)e xtended kappa-Poincare algebra (P) over tilde(kappa) and their implica tions for the existence of a first-order differential calculus. The ad ditional one-form needed to achieve a consistent calculus on kappa-Min kowski space is shown to be related to the additional central generato r entering in the (P) over tilde(kappa) Hopf algebra. In the process, deformations of the extended Galilei and Galilei algebras are introduc ed which have, respectively, a cocycle and a bicrossproduct structure. (C) 1995 American Institute of Physics.