The Coherence Threshold and the Physical Origin of Interiority

Consciousness is often approached through complex structural or informational frameworks, yet no minimal, substrate-independent physical condition has been widely established that specifies when an interior first appears. This paper introduces a dynamical threshold defined by the balance between internal restoration and environmental disruption. Let λ_self denote the rate of internal stabilization and λ_env the rate of environmental disruption. The relation R = λ_self / λ_env defines a critical condition R★ that separates externally driven from self-sustaining regimes. When R ≥ R★, system dynamics become dominated by internally generated structure, and prior states remain active in shaping future evolution, such that P(S_t | S_(t−1), S_(t−2), …) > P(S_t | E_t). In this regime, perturbations are resolved relative to the system’s own organization, establishing a physical reference frame defined from within. This constitutes self-measurement in a strictly dynamical sense and produces a minimal distinction between inside and outside. An interior is therefore identified with the condition in which a system’s states are defined relative to its own structure rather than solely by external influence. Consciousness corresponds to the operation of a system within this regime, where persistence, temporal depth, unity, and self-reference arise as direct consequences of sustained internal coherence. The coherence threshold provides a minimal, scale-invariant, and testable physical criterion for the emergence of interiority without introducing additional primitives.