Symmetries and Motions in Manifolds

In these lectures the relations between symmetries, Lie algebras, Killing vectors and Noether’s theorem are reviewed. A generalisation of the basic ideas to include velocity-dependend co-ordinate transformations naturally leads to the concept of Killing tensors. Via their Poisson brackets these tensors generate an a priori infinitedimensional Lie algebra. The nature of such infinite algebras is clarified using the example of flat space-time. Next the formalism is extended to spinning space, which in addition to the standard real co-ordinates is parametrized also by Grassmann-valued vector variables. The equations for extremal trajectories (‘geodesics’) of these spaces describe the pseudo-classical mechanics of a Dirac fermion. We apply the formalism to solve for the motion of a pseudo-classical electron in Schwarzschild space-time. Lectures at the 28th Karpacz Winterschool of Theoretical Physics (Poland, 1992), by J.W. van Holten Research supported by the Stichting FOM Address after oct. 1, 1992: Dept. of Mathematics, Science Labs., Univ. of Durham U.K. 1 Motions of Scalar Points in Curved SpaceTime 1.