# Open-graphs and monoidal theories†

@article{Dixon2013OpengraphsAM, title={Open-graphs and monoidal theories†}, author={Lucas Dixon and Aleks Kissinger}, journal={Mathematical Structures in Computer Science}, year={2013}, volume={23}, pages={308 - 359} }

String diagrams are a powerful tool for reasoning about physical processes, logic circuits, tensor networks and many other compositional structures. The distinguishing feature of these diagrams is that edges need not be connected to vertices at both ends, and these unconnected ends can be interpreted as the inputs and outputs of a diagram. In this paper, we give a concrete construction for string diagrams using a special kind of typed graph called an open-graph. While the category of open… Expand

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