Any good way to see 3d object that has no surface?

[arsenic]

In 4d there are a lot of 3d objects that have no surface to cover them
such as empty glome which has no surface
and a lot of 3d objects that has part of their volume which are not have
surface to cover them such as empty duocylinder which has two surface to cover them(the surfaces look like two empty spheres) but it's side is a volume that does not has any surface to cover it

Do you have any good way to understand those objects?

[Aale de Winkel]

the empty gongyl is the glome, which is the 4d-equivalent of the sphere, when it has no surface the object is non-existence and reverted to nill-space which is void and empty.

simular with the pentaspace "duocylinder" (alkaline hasn't updated the glossary yet) without a surface it, as well as the duocircle, reverts to nill-space.

As said nill-space is empty and void, so what is there to understand

Don't smell yourself and don't get nillified by arsenic poisoning :twisted: ( can this kind of suicide be done, probably you'll just double in strength )

As derived elsewhere the glome is isomorphic to a 3d filled beam (π,π,2&pi) (or perhaps better said filled double-cube, because one of its side is double the other two side) which is open at one (square) end.
The duocircle is isomorphic to the 2d filled square (2π,2π), so the pentaspace duocylinder a filled beam based on that square the third direction is of not specified length, so you could make it a filled cube.
All these objects are well understood. :wink:

[Keiji]

What he means is, a sphere has no edges on it so you can't map its net accurately on a piece of paper. Glomes have no faces on them so Emily couldn't map its net accurately on a swock.

[Aale de Winkel]

What he means is, a sphere has no edges on it so you can't map its net accurately on a piece of paper. Glomes have no faces on them so Emily couldn't map its net accurately on a swock.

if a sphere or glome has a hole in it, there is an edge (/wall?), but still won't map "accurately" onto the filled rectangle / beam. This is due to the curvature of the object and has nothing to do with wether or not the object has an edge. The hole will map onto some curve onto the rectangle, or whatever the map produces onto the beam on Emilies swock.
.