Bigraphs

Bigraphs are a graphical language for spatially distributed or concurrent systems, invented by Robin Milner to unify process calculi like the \(\pi\)-calculus. The name “bigraph” is supposed to evoke two superimposed graphs, a place graph and a link graph. This is somewhat misleading, as the place graph is actually a rooted forest and the link graph is actually a hypergraph. I think of a bigraph as an undirected wiring diagram with a forest structure on its boxes.

Literature

Introductions

  • Milner, 2009: Bigraphs and their algebra (doi, pdf)
    • Brief, mostly pictorial introduction to bigraphs
  • Milner, 2009: The space and motion of communicating agents (doi, draft )
    • His last major work, all about bigraphs and their applications
    • Milner, 2008, lecture notes based on book: Bigraphs: a model for mobile agents (pdf, slides)

Papers

  • Milner, 2009: Bigraphical categories (doi)
    • Abstract: “This short paper summarises the categories, and the functors between them, that represent the structure of that theory [of bigraphs].”