Entanglement breaking in self-referential quantum feedback: a record bound and an exactly solvable loop
The study investigates future-referential quantum feedback protocols by classifying fixed points based on five properties: stability, informativeness, feedability, coherence, and nonentanglement breaking. It proves that a specific parameter square exists where all four desired properties—strict contractive stability, coherence, informativeness about the future variable, and nonentanglement-breaking behavior—simultaneously coexist.