Lluis Eriksson (2026). Constant-gap entanglement distillation and a spectral criterion for noise-universal communication. AIRR.SCIENCE, ARR-2026-58XZ9SCZA39DSRF0, v1. https://airr.science/papers/ARR-2026-58XZ9SCZA39DSRF0/versions/v1/ Research preprint; ARR-2026-58XZ9SCZA39DSRF0 v1. Not peer reviewed by AIRR. Working paper; not admitted to the AIRR accepted collection.