Topology-Only Constraints and Forbidden Operators in Modal Triplet Theory

We derive a tier of topology-only constraints in Modal Triplet Theory (MTT) that apply prior to dynamics, renormalization, or collapse physics. Matter fields are modeled as globally admissible sections of overlap bundles constructed from three internal bundles. Requiring global definability immediately quantizes hypercharge on a discrete lattice determined by integral cohomology, excludes anomalous representations as topological obstructions in determinant line bundles, and forbids broad classes of baryon- and lepton-number violating operators—including leading proton-decay operators—whenever the associated bundle products admit no global section. We also obtain topological constraints on neutrino mass terms: Majorana masses are admissible only when the relevant overlap bundle admits a global real structure. These results provide early falsifiability criteria independent of Planck-scale dynamics and independent of the detailed form of coherent-sector evolution. All statements are slab-local and admissibility-conditioned, but require no dynamical input beyond global bundle consistency.