Some of us have been to those amusement park/carnival/theme park rides where you enter some capsule/machine, and you will float, etc.
There is also some other thing where you go inside a big room with normal gravity, and you are closed in and you start to float (i.e. no gravity), and the amount of gravity can be toggled by a person outside the room, or by some dial/switch, etc. It is like the picture I placed below.
I do not know what those things are called, and I will update accordingly when the names are presented, but what I am asking is how does that work?
How can the pull of gravity, result of the spacetime continuum affecting all bodies of mass, be artificially changed? If so, why don't we just alter gravity everywhere with these tools, and move giant, heavy objects easier and such?