Real Kasner and related complex ``windmill'' vacuum spacetime metrics
The metrics of \textit{T. Lewis} [Proc. R. Soc., Lond. Ser. A 136, 176-192 (1932; Zbl 0005.26905)] are shown to be Kasner metrics over the complex field. They admit a four-parameter local homothetic group of motions. The author calls them ``windmill metrics'' and discusses their null directions along with an extension to some other families of metrics.
scientific article; zbMATH DE number 95352
scientific article