Nonspherical perturbations of relativistic gravitational collapse
It is known that there can be no gravitational, electromagnetic, or scalar field perturbations (except angular momentum) of a Schwarzschild black hole. A gravitationally collapsing star with nonspherical perturbations must therefore radiate away its perturbations or halt its collapse. The results of...
Internet
https://thesis.library.caltech.edu/5526/1/Price_rh_1971.pdfPrice, Richard H. (1971) Nonspherical perturbations of relativistic gravitational collapse. Dissertation (Ph.D.), California Institute of Technology. doi:10.7907/1EGC-Y160. https://resolver.caltech.edu/CaltechTHESIS:01192010-090920179 <https://resolver.caltech.edu/CaltechTHESIS:01192010-090920179>