Biology as a Translator of Physical Noise: Stability Thresholds and the Φ ≈ 0.7 Release Boundary

This work investigates whether biological systems exhibit a consistent threshold separating sustainable regulation from physics-dominated dynamics. Across neural and cardiac observations, instability is analyzed as a function of normalized functional reserve (Φ). A reproducible transition appears near Φ ≈ 0.7. Above this value, systems maintain organized, low-variance behavior. Below it, stabilization rapidly deteriorates and dynamics revert toward underlying physical processes. The manuscript introduces the concept of a release boundary: a point at which continued regulatory effort becomes inefficient or structurally unsustainable. Rather than interpreting this transition as simple failure, the work proposes that biological regulation behaves as if it detects meaningful structure in stochastic variability and withdraws constraint when costs exceed benefits. The Φ ≈ 0.7 boundary is presented as an empirical regularity within the analyzed sessions. The broader interpretation — that biology functions as a “translator” of physical noise — is offered as a conceptual framework intended to generate testable predictions. The deposit includes: Full manuscript (PDF) Conceptual regime diagram Stress-test visualization Falsifiability criteria and experimental predictions This contribution is intended for discussion within systems biology, nonlinear dynamics, control theory, and complex systems research. The claims are explicitly testable and open to revision pending broader empirical evaluation.