Re Indexing the Inflation: A Structural Audit of Single Field Inflation Under Modern Constraints

Inflationary cosmology contains a vast catalogue of proposed inflaton candidates, many of which were introduced to satisfy specific observational or theoretical preferences. Claims of exclusion or viability are often tied to implicit assumptions about reheating, kinetic structure, initial conditions, or symmetry. This document re‑indexes the inflationary landscape by making these assumptions explicit. Using a finite set of model classes, an assumption matrix, and uniform closure criteria, the landscape collapses into a small number of structural equivalence classes. Plateau models, α‑attractors, and certain effective field theory expansions remain viable across broad regions of the assumption space. Large‑field monomial potentials and steep hilltop models are excluded under all reasonable assumptions. Natural inflation, hybrid inflation, and certain non‑canonical models survive only under specific or contrived conditions. The purpose of this work is not to select a preferred inflaton but to clarify the structure of the model space. Once assumptions are visible, the landscape becomes finite, coherent, and closed.