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Equational reasoning is central to quantum circuit optimisation and verification: one replaces subcircuits by provably equivalent ones using a fixed set of rewrite rules viewed as equations. A finite rule set is most informative when it separates the genuine algebra of a circuit fragment from the structural treatment of wires. This paper gives six near-Clifford fragments a common PROP treatment, where wire permutations are structural: qubit Clifford, real Clifford, Clifford+T (up to two qubits), Clifford+CS (up to three qubits), CNOT-dihedral, and qutrit Clifford. Starting from prior completeness theorems, we transfer completeness into this setting and remove redundant non-structural rules, then check minimality by separating interpretations tailored to individual axioms; the resulting presentations are minimal in all arities for qubit Clifford, real Clifford, and CNOT-dihedral, minimal in bounded ranges for the remaining fragments, and comparable by one transfer-and-separation pattern.
@InProceedings{blake:LIPIcs.FSCD.2026.6,
author = {Blake, Colin},
title = {{Simpler Presentations for Many Fragments of Quantum Circuits}},
booktitle = {11th International Conference on Formal Structures for Computation and Deduction (FSCD 2026)},
pages = {6:1--6:20},
series = {Leibniz International Proceedings in Informatics (LIPIcs)},
ISBN = {978-3-95977-433-8},
ISSN = {1868-8969},
year = {2026},
volume = {378},
editor = {Pfenning, Frank},
publisher = {Schloss Dagstuhl -- Leibniz-Zentrum f{\"u}r Informatik},
address = {Dagstuhl, Germany},
URL = {https://drops.dagstuhl.de/entities/document/10.4230/LIPIcs.FSCD.2026.6},
URN = {urn:nbn:de:0030-drops-263562},
doi = {10.4230/LIPIcs.FSCD.2026.6},
annote = {Keywords: Quantum circuits, Clifford group, equational theories, minimality, qutrit}
}