Correct, that’s not a hole in the topological sense. A famous example is a coffee cup: the handle is a (through-) hole, but the inside of the cup is not. As such, the coffee cup is isomorphic (=identical in terms of their overall structure) to a donut.
Topological holes are through-holes. If there is no exit, you could continuously deform the shape until the hole is gone
So if i dig a hole in the ground that’s not a hole? Should we pivot to divot?
Correct, that’s not a hole in the topological sense. A famous example is a coffee cup: the handle is a (through-) hole, but the inside of the cup is not. As such, the coffee cup is isomorphic (=identical in terms of their overall structure) to a donut.