Holonomy and projective symmetry in space-times
arXiv:gr-qc/0406082 · doi:10.1088/0264-9381/21/19/004
Abstract
It is shown using a space-time curvature classification and decomposition that for certain holonomy types of a space-time, proper projective vector fields cannot exist. Existence is confirmed, by example, for the remaining holonomy types. In all except the most general holonomy type, a local uniqueness theorem for proper projective symmetry is established.
LaTex2e, 12 pages