Dark Matter Effects without dark Matter

Proposed is a covariant vacuum-reaction framework in which galactic-scale gravitational anomalies emerge not from non-baryonic dark matter particles, but from dynamical polarization states of the spacetime vacuum itself. In this approach, baryonic matter acts as a source term that induces local vacuum polarization fields whose collective dynamics generate additional effective curvature. The resulting emergent gravitational sector reproduces flat galactic rotation curves, naturally yields baryonic Tully–Fisher scaling, and can produce gravitational lensing signatures without requiring collisionless particle halos. The model extends General Relativity (GRT) through a dynamical scalar vacuum field coupled nonlinearly to curvature and matter. Unlike algebraic modified-gravity approaches, the vacuum polarization field possesses independent energy density, propagation dynamics, relaxation timescales, and nonlocal memory behavior. This allows partial dynamical separation between baryonic matter and effective gravitational structures, potentially addressing systems such as the Bullet Cluster. Also formulated is a minimal covariant action, derived are the associated field equations, investigated the weak-field galactic limit, and discussed are implications for cosmology, structure formation, and vacuum-mediated emergent gravitation. The framework suggests that dark-matter phenomenology may arise from collective vacuum degrees of freedom rather than undiscovered black, dark particles. In this way dark matter phenomenology could be observed without any existence of baryoniclike DM. A larger article to this theme will be prepared and follow.