Termination of Graph Transformation Systems using Weighted Subgraph Counting

We introduce a termination method for the algebraic graph transformation framework PBPO+, in which we weigh objects by summing a class of weighted morphisms targeting them. The method is well defined in rm-adhesive quasitoposes (which includes toposes), and is applicable to non-linear rules. The method is also defined for other frameworks, including DPO and SqPO, because we have previously shown that they are naturally encodable into PBPO+ in the quasitopos setting.