On limits of spacetimes-a coordinate-free approach
On limits of spacetimes-a coordinate-free approach
A coordinate-free approach to limits of spacetimes is developed. The limits of the Schwarzschild metric as the mass parameter tends to 0 or infinity are studied, extending previous results. Besides the known Petrov-type-D and type-O limits, three vacuum plane-wave solutions of Petrov type N are found to be limits of …