A solution of a problem of Sophus Lie: Normal forms of two-dimensional metrics admitting two projective vector fields

摘要

We give a complete list of normal forms for the two-dimensional metrics that admit a transitive Lie pseudogroup of geodesic-preserving transformations and we show that these normal forms are mutually non-isometric. This solves a problem posed by Sophus Lie. © 2007 Springer-Verlag.