Proved the three-qubit Shifts UPB projector witness is optimal by determining its complete equality set of 8 product rays spanning the full Hilbert space, with exact white-noise detection thresholds through exact symbolic computation.

Proved the three-qubit Shifts UPB projector witness is optimal by determining its complete equality set of 8 product rays spanning the full Hilbert space, with exact white-noise detection thresholds through exact symbolic computation.