Active Geometry Without a Preferred Frame: A Tetrad–Connection Formulation

This work presents a structural formulation of an active geometric framework based on a dynamical tetrad–connection description of spacetime. A localized geometric object carrying an internal Lorentz frame is introduced, and its interaction with geometry is described through a covariant transport-mismatch variable. The framework is shown to be generally covariant, locally Lorentz invariant, and free of any preferred timelike structure. The paper establishes a consistency result rather than a physical proof: it demonstrates that active geometry and the absence of an ether are structurally compatible and that a local geometric interpretation of inertia can be formulated under explicitly stated assumptions. No quantitative law of inertia, inertial mass, Newtonian limit, or experimental predictions are claimed.