Manuscript Oai280-C@1 · Oai280-C.tex · section · 7d44b8c0

Approximation comparison ledger

Approximate-recovery examples on the declared models › Approximation comparison ledger · lines 1800–1823

Declared channel/model	Specified error	Status
Ideal five-qubit triple	$0$	Unique complete decoder; resource restrictions stated separately
Logical Pauli insertion	$1 - p_{I}$	Exact error for the printed decoder
Logical coherent rotation	$∣ sin (θ /2) ∣$	Specified decoder only; known inverse can improve it
Flagged triple erasure	$3 p /4$	Optimal over all CPTP decoders
Controlled spectator phase before $W$	$1$	Fixed spectator $0$ would conceal the failure
Successful branch with replacement failure	$3 (1 - η) /4$	Complete returned channel, with flag discarded