Lluis Eriksson (2026). The Vacuum Was Never Absent: A Machine-Checked Perron Theorem for Strictly Positive Kernels, and the Coupled-Slice Vacuum at Every Spatial Extent. AIRR.SCIENCE, ARR-2026-2YDE42KFDY8Y3AA0, v1. https://airr.science/papers/ARR-2026-2YDE42KFDY8Y3AA0/versions/v1/ Archived manuscript; ARR-2026-2YDE42KFDY8Y3AA0 v1. Not peer reviewed by AIRR. Historical import; not assessed by AIRR.