It is unknown whether or not every polycube has an edge-unfolding. A polycube is an object constructed by gluing cubes face-to-face . An edge-unfolding cuts edges on the surface and unfolds it to a net, a non-overlapping polygon in the plane. Here we explore the more restricted edge-unzippings where the cut edges  form a path . We construct two different polycubes neither of which has an edge-unzipping .
It is unknown whether every polycube (polyhedron constructed by gluing cubes face-to-face ) has an edge unfolding, that is, cuts along edges of the cubes that unfolds the polycube to a single nonoverlapping polygon in the plane. Here we construct polycubes that have no *edge zipper unfolding* where the cut edges are further restricted to form a path .
R
or not every polycube has an edge-unfolding. A polycube is an object
every polycube (polyhedron
R
. An edge-unfolding cuts edges on the surface and unfolds it to a net, a non-overlapping
) has an edge unfolding, that is, cuts along edges of the cubes that unfolds the polycube to a single nonoverlapping
R
explore the more restricted edge-unzippings
construct polycubes that have no *edge zipper unfolding*
A
are further restricted to
D
. We construct two different polycubes neither of which has an edge-unzipping