Spokes

3

Analysis

PAPER

Directed Gate Graph

Node Classification

Theorem 2: Relay Load → Fidelity Cost

THE RELAY-BIT PRINCIPLE

A qubit propagates errors if and only if it serves as a CNOT control after serving as a target. r(q) = 1 → relay → propagates. r(q) = 0 → hub or spoke → fault-isolated. Circuits with zero relays achieve total fault isolation at zero additional cost.