Causally verified distributed boundary memory and paid self-maintenance in a finite simulated medium

Abstract

We report, in a finite designed reaction–diffusion medium on a 64×64 lattice, a distributed physical memory that lives in the configuration of a flow-constructed boundary rather than in any object, label, or instruction store. A directed flow writes a local orientation field into boundary material; after the originating flow is removed and the medium relaxes, an identical weak, direction-free scalar input recovers opposite motions depending only on the boundary's history. The effect is causally necessary: resetting the boundary, shuffling its local orientation, or disabling its plasticity abolishes recovery, and a fixed-protocol permutation test (statistic and one-sided alternative fixed in advance) gives per-seed p ≤ 5×10⁻³ across eight independent seeds with large effect sizes. In an autonomous extension, boundary memory continuously gates permeability, acquired resource drives motion, and motion pays for repair of the boundary that stores the memory, closing a self-maintaining loop that survives repeated damage. Results rest on gates and thresholds fixed before the confirmation runs, disjoint development/confirmation seed families, and a conserved resource ledger in the autonomous stage (B1). We do not claim natural occurrence, open-ended evolution, spontaneous birth of the carrier, or new physical laws; the contribution is the causal-necessity protocol and its transportable operational definition of configuration memory. This study is one component of a broader, open-ended research program exploring the possibility space of non-genomic organization — memory, self-maintenance, and selection-like dynamics that need not rely on a genome. The present preprint establishes only the distributed-memory component and makes no claim about evolution, inheritance, life, or natural occurrence.