Graphical Quadratic Algebra — Dario Stein, Fabio Zanasi, Robin Piedeleu & Richard Samuelson (2024). arXiv:2403.02284 (v3, PDF).
Gives a complete diagrammatic axiomatisation of quadratic relations, extending the graphical algebra of linear relations with a probabilistic (Gaussian) layer, so that noise, exact constraints and uninformative priors are all string diagrams with sound and complete equations.
Sources: the paper, arXiv:2403.02284v3, checked against the arXiv listing. Index: Papers.
Key definitions and results
- Complete axiomatisation of quadratic relations