Well, if I remember my graph theory well enough, if A is the adjacency matrix of the graph, each entry of A^n is the number of ways to get between the corresponding nodes in n steps or less. So ...

These issues involve dividing a graph’s vertex set into distinct subsets that optimise specific criteria, such as minimising inter-part edge counts or balancing the sizes of the resulting parts.

Bisection: A type of graph partitioning that splits the vertex set into two parts of nearly equal size, typically with the aim of minimising inter-part edge crossings.