UED Reconstruction Programme — Paper 19: Dynamic Chavan Windows and ATT-Regulated Persistence

Paper 19 of the UED Reconstruction Programme extends the static persistence architecture of Papers 15–18 into changing environments. Rather than treating a persistent manifestation as a frozen configuration, it allows the lower and upper Chavan Limits to depend on surrounding geometry and asks whether physical identity can remain preserved while the corresponding viability window moves. The paper introduces a normalized Chavan coordinate that separates the absolute SVE-control state from a manifestation's relative position within its own persistence window. Exact window kinematics show that a manifestation can preserve the same relational state while its absolute control variables change, provided the state and its viability geometry co-move. Alignment Threshold Time (ATT) is then applied as the first-passage duration required for a disturbed manifestation to re-enter a declared tracking tolerance around a preferred branch state. A moving environment produces a finite tracking lag. When this finite response time is combined with the critical slowing established in Paper 16, the dynamically usable Chavan window becomes narrower than the static existence window. A rate-dependent dynamic safety margin is derived. For fold-like critical slowing, the contraction of the usable persistence region scales with the two-thirds power of the normalized environmental sweep rate. A manifestation can therefore become dynamically nonviable before reaching its instantaneous static Chavan Limit. The causal branch dynamics also clarify the meaning of internal “breathing.” In a positively damped static window, oscillation is transient rather than self-sustained. Persistent bounded oscillation requires continuing environmental drive, negligible dissipation, retained internal exchange, or another independently measurable mechanism. Persistence itself therefore does not require breathing. Effective mass is treated as a response of the moving persistent branch rather than assumed constant. The Paper-16 numerical branch exhibits substantial variation in its shape-inertia norm, so environmental mass invariance requires a measurable covariance, compensation, plateau, or extension of the state description. Finally, Paper 19 distinguishes action selection from action preservation. Paper 18 showed that the present SVE closure does not select a universal nonzero action quantum. Paper 19 shows instead that, once an action has been independently selected, slow environmental change can preserve it through classical adiabatic invariance. This provides a possible mechanism for environmental stability of an action scale without constituting a derivation of Planck’s constant. Paper 19 therefore gives a dynamic mathematical meaning to persistence: what persists need not remain unchanged in absolute state; it must re-resolve rapidly enough to remain within its moving viability geometry.