Talk:Vacuum Airships (Terra Futura)/@comment-81.249.251.203-20140427223329/@comment-72.64.235.88-20140710063721

Actually, you'd be wrong. By creating a vacuum inside an object, and assuming the object doesn't implode, you can reduce the avrrage density of the overall space the object and contained vacuum occupy. If the non-imploding vacuum-containing structure has low enough mass, and is sufficiently large, you end up with an average density lower than that of air, causing the shell and it's contained vacuum to rise relative to the nearest sufficiently large source of gravitational force (e.g., up relative to the surface of Earth).