Something I don't understand, if a wormhole exists in 3d space connecting 2 points over vast distance, does all the space between the 2 points become part of the wormhole. If the wormhole exists purely in 3d space it'd need to occupy all the space between those 2 points in our 3d universe.
The example of folding a sheet of paper and poking a pen through it is an example of 2d space being folded in 3 dimensions. For that type of wormhole to exist in our universe, our universe must have a hidden/inaccessible 4th spatial dimension that is being bent/warped.
