The lattice of d-structures

The set of d-structures on a topological space form a lattice and in fact a locale. There is a Galois connection between the lattice of subsets of the space and the lattice of d-structures. Variation of the d-structures induces change in the spaces of directed paths. Hence variation of d-structures and variation of the “forbidden area” may be considered together via for instance (co)homology and homotopy sequences.