Muon g-2 Mystery Reborn: Lattice QCD Aligns with Experiments, Old Data-Driven Predictions Clash

New lattice QCD calculations explain the muon g-2 excess without invoking new particles, aligning with Fermilab’s precise measurement and challenging the older data-driven predictions that relied on electron-positron collision data; at the same time, fresh VEPP-2000 pion-production results and divergent collider measurements renew tensions across experiments, hinting at either unknown particles or overlooked experimental details and underscoring four decades of conflicting data that physicists still need to resolve.