and you can do one better than that - Birkhoff's theorem, the relativistic analogue of the shell theorem. https://en.wikipedia.org/wiki/Birkhoff%27s_theorem_(r

and you can do one better than that - Birkhoff's theorem, the relativistic analogue of the shell theorem. https://en.wikipedia.org/wiki/Birkhoff%27s_theorem_(relativity) https://en.wikipedia.org/wiki/Birkhoff%27s_theorem_(relativi...