Universality Under Selection: Why Widely Separated Physical Systems Share the Same Statistics

Empirically, systems spanning many orders of magnitude in scale—earthquakes, neuronal avalanches, financial crashes, sonoluminescence flashes, fast radio bursts, and black hole accretion events—exhibit remarkably similar statistical signatures: heavy-tailed event energies, non-Poissonian waiting times, burst intermittency, and scale-invariant structure. This paper shows that such universality does not arise from shared microphysics, but from shared selection geometry. Within the Universal Selection Operator (USO) framework, I demonstrate that these statistics are invariants of the loss operator K, not of the Hamiltonian dynamics. Universality classes are therefore defined by the geometry of survival, not by forces, fields, or constituents.