I have seen discussions on here and online about vacuum buoyancy and had 3 questions:
1. Can a vacuumed out cavity be created on earth or just less of what was vacuumed out? I ask because I am thinking that if you created a container underwater with water in it, if you try to evacuate all water from the container with a vacuum (not by pumping in air), what would happen to the water inside?
2. If a structure meant for vacuum buoyancy cannot withstand atmospheric pressure near sea level when a vacuum is attempted to be created, what would happen if that structure (while open) was taken up in a weather balloon where atmospheric pressure can be far less http://www.altitude.org/air_pressure.phpand then sealed and then a vacuum attempted again? What would happen once it is dropped?
3. What would happen if a structure with a large enough cavity (to dispace more air [N/O/CO2/H2O/etc] than it weighs) were 3d printed in space with a seal so no gases can enter and then descended into earth's atmosphere? Will it float, collapse, or something else?
