something that cant be reduced would be the only entity, all other things are assemblages of that entity, the problem of variability occurs, if you can observe at the scale of absolute fundamental structure, how can difference occur?
And by difference, I mean, establish boundaries between objects.
the geometric structure of spacetime at planck scale is problematic, considering how you might visualise a planck polyhedron so that no space is defined in less than whole planck units i.e. all dimensions of length are whole numbers.
you have to do some topological trickery to make a discreet planck volume that works.