Causal Interaction and the Limits of Observability

Key Points

• The aim is to develop a framework that clearly distinguishes between causal interaction and observability in physical systems.
• Developed an information-theoretic framework for analysis.
• Defined observability using mutual information concepts.
• Used examples from cosmological horizons and quantum no-signaling to illustrate limitations.
• Identified conditions where systems can be unobservable even while engaging in causal processes.
• Demonstrated the implications for epistemic accessibility in established physical theories.