Graphical Language with Delayed Trace: Picturing Quantum Computing with Finite Memory

@article{Carette2021GraphicalLW,
  title={Graphical Language with Delayed Trace: Picturing Quantum Computing with Finite Memory},
  author={Titouan Carette and Marc de Visme and Simon Perdrix},
  journal={2021 36th Annual ACM/IEEE Symposium on Logic in Computer Science (LICS)},
  year={2021},
  pages={1-13}
}
Graphical languages, like quantum circuits or ZX-calculus, have been successfully designed to represent (memoryless) quantum computations acting on a finite number of qubits. Meanwhile, delayed traces have been used as a graphical way to represent finite-memory computations on streams, in a classical setting (cartesian data types). We merge those two approaches and describe a general construction that extends any graphical language, equipped with a notion of discarding, to a graphical language… 

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