I want to first say something about the abstract setting. In the arXiv paper (arXiv:0909.4136 ) we considered a more complicated notion of process (mentioned in the second post of this series) with nine graphs, and we described many operations. We now believe that this definition was too general, and instead a process should consist of five graphs A,B,X,Y, G and four morphisms δ0
: G → A, δ1
: G → B, γ0
: X → G, γ1
: Y → G as we have been discussing in these posts.
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