Physical Articulation of the Indexical-Fiber Framework

The Physical Articulation states where the indexical-fiber framework meets working physics: the algebraic register it operates at and the closures it declines; the inheritance of the Born measure through Gleason's theorem and the boundary of that inheritance; the topological sector and why it carries no predictive bite; which dynamics are foreclosed and which remain; the framework's exposure to collapse-model experiment; and the exact price of its immunity. It adds no new empirical prediction.

Rev 2.4 places the index at the observer: it is zero on every loop around the edge of an observer's causal diamond and at a black hole's bifurcation surface, so it contributes nothing to the thermal condition; read as a spin-structure choice, the twist around such an edge sits with the physical spin structure. Its parent paper is Definiteness as Index, Rev 4.1.