Horizons and the Limits of Public Finality: Black Holes, Rindler Wedges, and Cosmological Causal Patches

This paper develops an interpretive typology of horizons based on a distinction between direct causal access, indirect reconstructive access, recoverability, and public finality. Its central claim is limited: a horizon does not create, destroy, or finalize a record. It constrains the causal channels through which signals and records can reach an observer confined to a worldline or causal patch, and therefore constrains public finality only derivatively. Three cases are distinguished. For an evaporating black hole, direct causal access across the horizon is not restored, but controlled island and quantum-extremal-surface models allow an interior region to become reconstructible from the Hawking radiation after the Page transition, with qualifications. This is delayed reconstructibility rather than redundant public finality. For an eternally uniformly accelerated observer, a Rindler horizon produces observer-relative causal exclusion, while suitable inertial observers face no corresponding boundary and indirect records may remain available. For an observer in a cosmology with finite future conformal time, a cosmological event horizon produces asymptotic causal exclusion of direct signals, while reconstruction from static-patch or horizon degrees of freedom remains unresolved. The paper argues that these horizons should not be identified. Their common feature is only that each limits direct causal access within a specified observer-accessible region. The cosmological interpretation is explicitly more conjectural than the black-hole and Rindler analyses. The framework infers inaccessibility rather than destruction, derives no horizon entropy, temperature, or information-recovery law, does not establish de Sitter holography, and makes no independent empirical prediction.