Projected Gravity from a CPT-Conjugate Spacetime: A Unified Framework for Baryon Asymmetry and Cosmological Missing Mass

Modern cosmology is challenged by two fundamental anomalies: the apparent absence of primordial antimatter (Baryon Asymmetry) and the unexplained gravitational effects attributed to invisible "Dark Matter". This paper proposes a unified solution rooted in CPT symmetry and the Feynman-Stueckelberg interpretation of antiparticles. We postulate that the Big Bang produced a CPT-symmetric universe consisting of two temporal branches: our universe ($M_+$), where matter evolves forward in time, and a conjugate branch ($M_-$), where antimatter evolves backward in time. We demonstrate that while electromagnetic interaction is prohibited between these branches due to temporal divergence, gravitational interaction remains intact via the shared spacetime metric. Consequently, the "missing" antimatter exists in $M_-$ and exerts a gravitational influence on $M_+$, manifesting precisely as the phenomenon currently identified as Dark Matter3.