Radial conformal Killing vectors in spherically symmetric shear-free space-times
The conformal Killing equations are reduced to a system of 2 coupled differential equations whose coefficients depend on only one combination of the metric variables. 3 solutions (i.e. conformal Killing vectors) exist for subclasses of conformally flat space-times (including Friedman- Robert-Walker metrics), 1 for a class of selfsimilar metrics. In the general case, at most one conformal Killing vector is possible, but this case could not be integrated.
scientific article; zbMATH DE number 4117428
scientific article