Observable Horizons and Structural Walls in Reduced Inverse Geometry

This repository contains the manuscript source, compiled PDF, figures, and supporting materials for the paper on dual limits in reduced inverse geometry. The paper develops a unified reduced-geometric framework for two distinct failure mechanisms in inverse reconstruction: geometric interfaces and noise-relative horizons. The first appears as a finite, immovable boundary in reduced reheating geometry, while the second appears as an operational, movable limit in dynamical-decoupling noise spectroscopy. The central result is a dual classification theorem showing that these two systems jointly realize the full reduced-geometry taxonomy of obstruction mechanisms. The deposit includes the LaTeX source, compiled manuscript, figure files, and associated supporting materials used in the preparation of the paper. V2: The paper has been substantially reorganized around the distinction between structural walls and observable horizons in reduced inverse geometry. The previous Fisher/rank-centered framing has been replaced by an operational comparison between asymptotic sensitivity suppression in DD spectroscopy and finite branch-wall closure in reheating inverse geometry. The revised version introduces a unified operational vocabulary for system-dependent sensitivity measures, clarifies the role of asymptotic versus finite structural walls, strengthens the DD finite-collapse analysis, refines the fold-interface interpretation in reheating geometry, and updates all conceptual figures and cost-scaling discussions for consistency and readability.