Characterization of three-dimensional Lorentzian metrics that admit four Killing vectors
arXiv:1903.10496
Abstract
We consider three-dimensional Lorentzian metrics that locally admit four independent Killing vectors. Their classification is summarized, and conditions for characterizing them are found. These consist of algebraic classification of the traceless Ricci tensor, and other conditions satisfied by the curvature and its derivative.
15 pages