String diagrams are a graphical representation of morphisms in monoidal categories. Formally they are geometric embeddings of graphs in the plane, which means they are invariant under topological moves (which is the secret to their usefulness). But aesthetic beauty is not invariant under topological moves, and I put a lot of craftsmanship into my TikZ code. On this page I collect my favourite examples. At the moment these are all mine (a couple were typeset by my coauthors), but in the future I plan to ask others for permission to use their diagrams if I find them beautiful.
See also Paul-André Melliès’ similar gallery. Obviously I’m not claiming that these are actually art (merely design), but see also the work of Bernar Venet.
From my unpublished notes
From my unpublished notes
From my unpublished notes
From my unpublished notes
From my unpublished notes
From Compositionality and string diagrams for game theory
From Compositionality and string diagrams for game theory
From Compositionality and string diagrams in game theory
From Compositionality and string diagrams for game theory
From Coherence for lenses and open games
Jules Hedges 