On the Emergence of the Orthogonal Decomposition Formula of World Quantum Theory from Envelope Interface Nesting Structure

WQT takes c² = v² + d² as Postulate II. This paper demonstrates that it is not a postulate, but a direct consequence of the Meridian Touching Wave Packet velocity decomposition. The proof requires only one step: the Meridian Touching Wave Packet resultant velocity decomposition is Cu² = Vu² + Du² + Su²; from the definition of the Meridian Touching Wave Packet center-radial resultant velocity Nu² = Du² + Su², direct substitution yields Cu² = Vu² + Nu²; through the bridge relation D0 = Cu, mapping D0→c, Vu→v, Nu→d, we obtain c² = v² + d². Keywords: orthogonal decomposition, Meridian Touching Wave Packet, bridge relation, WQT Postulate II