Horizons as Event Density Decoupling Surfaces

This paper is ED‑06 in the Event Density Framework. Horizons are usually treated as geometric artifacts of spacetime or coordinate singularities. In the Event Density (ED) ontology, they arise for a deeper reason. ED takes becoming—the continual production of micro‑events—as primitive, with spacetime emerging as the macroscopic shadow of ED gradients. A horizon forms when these gradients become so steep that participation can no longer be reconciled across a boundary. The flow of becoming becomes one‑way: influence can cross in one direction but not the other. This paper develops horizons as ED decoupling surfaces—regions where participation fractures, information flow becomes asymmetric, and the spacetime approximation fails. Black hole horizons, Rindler horizons, and cosmological horizons all appear as instances of the same structural phenomenon: discontinuities in the ED field. This reframing dissolves traditional puzzles about horizons and clarifies why they encode information, generate thermodynamic behavior, and mark the limits of classical geometry.