On Term Graphs as an Adhesive Category

Andrea Corradini, Fabio Gadducci
2005 Electronical Notes in Theoretical Computer Science  
The recent interest in bisimulation congruences for reduction systems, stimulated by the research on general (often graphical) frameworks for nominal calculi, has brought forward many proposals for categorical formalisms where relevant properties of observational equivalences could be automatically verified. Interestingly, some of these formalisms also identified suitable categories where the standard tools and techniques developed for the double-pushout approach to graph transformation [9]
more » ... d be recast, thus providing a valid alternative to the High-Level Replacement Systems paradigm [11] . In this paper we consider the category of term graphs, and we prove that it (partly) fits in the general framework for adhesive categories, developed in [19, 26] , extended in [12] and applied to reduction systems in [24] . The main technical achievement concerns the proof that the category of term graphs is actually quasi-adhesive, obtained by proving the existence of suitable Van Kampen squares.
doi:10.1016/j.entcs.2005.02.014 fatcat:rykwyd5jwzdprpzf3dx6wz4tvi