Boundary Provenance Relations

Spatially nested objects splitting and merging have been studied formally as relations between nodes of adjacency trees representing the start and end states of a process. This gives provenance for objects at the end -- specifying those objects at the start which were involved in the formation of those at the end. This paper shows that using relations between edges as well as nodes of the trees gives a more informative model. The appropriate kind of relation between trees is identified, and sequences of atomic changes (merging, splitting, creation and destruction as well as no change) are shown to be sufficient to generate all possible relations of this particular kind between adjacency trees