Complex amplitudes (modulus vs phase)

• Modulus $|ψ|²$: objective outcome statistics (Born rule).
• Phase arg $ψ$: context‑sensitive relations among alternatives; becomes observable via interferometry and basis choice.

Agent choices (basis, interferometry)

• Choice of measurement basis/configuration exposes different relations as Text.
• Adaptive, model‑driven basis selection can be framed as closing the loop.

Measurement as closing the loop

• Operationally: agent picks a basis, registers an outcome, and optionally uses it for feedback (quantum trajectories with control).

Resource viewpoints (coherence, information)

• Convert coherence (off‑diagonals) into work/information under control constraints.
• Track efficiency and robustness under noise.

Further reading: Quantum Control & Feedback, Operational Criteria, Research Directions (quantum tracks), Glossary.