Blind Quantum Computing 2D: Cluster-State Trap Detection

A client with only the ability to prepare single qubits can hand an entire computation to a powerful quantum server on the quantum internet — without the server ever learning the input, the output, or the program. This 2D companion to the full UBQC (Universal Blind Quantum Computing) simulator draws the same brickwork cluster-state graph flat, as a pannable, zoomable lattice: rows of qubits are wired into a 2D graph with CZ entangling gates, then measured column by column in bases masked by a one-time random pad, so every angle the server sees is uniformly random and carries zero information about the real computation. Gold trap qubits — decoys with a known expected outcome — are woven into the same graph, and toggling the server to "cheating" shows their failure rate climb, which is exactly how a client statistically catches a dishonest server without ever seeing inside it.