Dehn functions of coabelian subgroups of direct products of groups

We develop new methods for computing the precise Dehn functions of coabelian subgroups direct products groups, that is, which arise as kernels homomorphisms from product onto a free abelian group. These improve and generalise previous results by Carter Forester on level sets in simply connected cube complexes, Bridson cocyclic groups Dison groups. then provide several applications our to with interesting geometric finiteness properties right-angled Artin