High gravity as a substitute for high speed relatistic time dilation effect From the article Using time dilation under the Theory of General Relativity for instance Residing inside of a hollow high mass object Are you sure this is accurate I was under the impression that according to the shell theorem the net gravity inside a hollow symmetrical sphere was zero If the hollow object isn t symmetrical there could be some gravity inside but in that case it would be no different from and probably less efficient than standing on the outside of a high mass object