A Smooth 5D Braneworld Black Hole Model with a Horizon Brane-Bulk Transition Mechanism

We propose a speculative 5D braneworld black hole model in which the observable 3 + 1- dimensional universe is represented as a brane embedded in a higher-dimensional bulk space time. Within this framework, we construct a smooth, horizon-regular warped metric with two tunable dimensionless parameters: a brane-bulk coupling parameter γ and a bulk parity breaking parameter α. The model is designed so that, for non-zero parameter values, the near-horizon region can support nontrivial bulk-directed evolution for causal geodesics that originate on the brane, while the classical Schwarzschild singularity is regularized within the model geometry. In the far-field limit, the induced brane metric recovers standard Schwarzschild behavior asymptotically. We emphasize that this work does not establish that astrophysical black holes are inter-dimensional portals, nor does it claim a universal theo rem about gravity. Rather, it formulates a falsifiable hypothesis within higher-dimensional gravity and braneworld geometry, with potentially testable observational consequences for black hole shadows and gravitational-wave signals.