Causal-Order Identification of Memoryless Sequential Quantum Processes from Restricted Projective Data

arXiv:2605.04571 · quant-ph · Submitted 2026-05-06 · Read on arXiv

quant-ph

Submitted: 2026-05-06

Updated: 2026-09-30

Comments: Minor errors were corrected

License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/

Terminology

• Consistency — 20× in this paper · explained in 3 episodes
• Temporal Correlations — 5× in this paper · explained in 2 episodes
• Trace — 5× in this paper · explained in 2 episodes
• Causal Inference — 3× in this paper · explained in 4 episodes
• Adaptive Strategy — 2× in this paper · explained in 1 episode
• Verification — 2× in this paper · explained in 2 episodes
• Generalization — 1× in this paper · explained in 13 episodes
• Generative AI — 1× in this paper · explained in 2 episodes
• Process tomography — 1× in this paper · explained in 2 episodes

Sources

• Quantum correlations with no causal order
• Strict hierarchy between parallel, sequential, and indefinite-causal-order strategies for channel discrimination
• Enhanced communication with the assistance of indefinite causal order
• Unitary channel discrimination beyond group structures: Advantages of sequential and indefinite-causal-order strategies
• Quantum Metrology with Indefinite Causal Order
• Quantum Refrigeration with Indefinite Causal Order
• Characterization-free classification and identification of the environment between two quantum players
• Connecting processes with indefinite causal order and multi-time quantum states
• On quantum states over time
• From time-reversal symmetry to quantum Bayes' rules
• Operator representation of spatiotemporal quantum correlations
• Bipartite quantum states admitting a causal explanation

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