I’m going to assume by “matter” you mean “objects”, if not please correct.
Good distinction, and for now I’m going to go with “matter”, though it may be interesting to later consider objects.
Space cannot be the same as objects
You’re right, but that’s not the claim.
Are the fundamental constituents discrete or continuous? Are you asking if the universe is composed of disconnected, separate entities or of interconnected ones?
Not about connectedness, but about whether you can have space (or matter, or objects) which can be mapped into ℝ3 (or ℝ4). That is: Can there be an object such that the point-sized constituents of it are isomorphic to the points of the graph of x2 + y2 + z2 = 1? If not, then the objects must be mapped onto ℚ, which would be weird, or ℕ.
What do you mean [by “is matter gunky”]?
“Gunk” is a technical term meaning non-atomistic. I.e. infinitely decomposable.
In any case, my broader point was to object to reasoning about physical objects by assuming that they have some kind of reified mathematical boundary (discrete or continuous) and deriving case conclusions as you did earlier in this thread. Moreover, I believe that speaking about “continuous objects” is vulnerable to the same kinds of objections as “exact measurement” is.
I agree, perhaps, with the larger point. (I think smaller points have been addressed above.) My position is that this question employs topological or geometric concepts in order to settle questions about physics or kinematics. That’s just folly. Geometry does not tell you what happens when things interact, it just describes surfaces and solids in a mathematical framework which is supposed to have useful applications to the real world (but not necessarily imply any perfect isomorphism to the real world).
The point against this, though, is that we want to consider what is metaphysically possible, not just physically possible. And so we want an answer to whether we can, by conceptual analysis, rule out the possibility of an object being an open surface, and if not, then what should happen when they approach each other at a constant rate of speed with no repulsive forces? But again, I take the question to be confused, because the concepts that we are using to describe the situation do not give us an answer, so conceptual analysis cannot give an answer. If you build into the situation that it is an open sphere which cannot be collocated, then you are on your way to an answer (vacuously). And so on.
Additionally groups, groupings, and group hierarchies are conceptual, and concepts are not objects.
So a group of pencils is a concept and not an object? Sure, the formation of groups as a mental act may be conceptual, but the groups themselves are just stuff.