Paper 115: Toward Many Magnitudes Lower-Energy Fusion via Corridor-Gated Transport: A Locked Toy Model with Junction Switching and Timing-Domain Witnesses

This paper presents a corridor-gated framework for interaction triggering in which successful events depend on compatibility along viable transport paths rather than solely on bulk conditions such as temperature or confinement. We formalize this idea with a locked, reproducible toy model (Toy Model v6) that introduces an acceptance-based conductance variable to quantify the fraction of structurally admissible encounters. The model explicitly separates throughput (governed by conductance) from routing (governed by junction competition) and introduces a timing-domain witness for route switching under realistic measurement jitter. Across multiple independent control families, yield proxies collapse onto conductance, routing can be modulated without throughput collapse, anisotropy-only controls act as negative tests, and switching produces discrete delay modes that remain instrument-readable. No fusion experiments are reported. Instead, the paper provides falsifiable predictions and a staged validation program—spanning simulation-first tests, low-cost photonic/RF analogs, and fusion-adjacent diagnostics—focused on interaction economics and neutron load compression rather than net-energy claims. The primary contribution is a mechanism-level, audit-grade framework that enables open scrutiny and replication.