Definition: Ledgers

The decoder live-register peak is the maximum, over branches and times, of the number of decoder-held qubits. It includes fresh ancillas and returned output registers. Unarrived source registers are listed separately in a source-storage ledger; they cannot be operated on before arrival.

The storage ledger records every register's holding interval and location. The classical ledger records outcome alphabets and messages. A total experiment-storage claim must include both decoder storage and parked source storage. A decoder peak is not, by itself, a bound on total physical storage.