Standard physics identifies a particle by its quantum numbers and treats this identity ascontext-independent: an electron in a hydrogen atom, an electron in a crystal lattice, and a "free" electron ina conductor are all "the same electron." Building on the constraint ontology developed in a companion paper— in which the physical world consists of a field and constraints upon it, and particles are constraint patterns("knots") in the field — this paper argues that "electron" names a binding pattern, not a persistent entity. Thefield excitation (energy carrying conserved quantum numbers) is a common substrate; the binding is whatdifferentiates. Different bindings constitute different electrons, and mass is a property of the binding, not ofthe bound. The effective mass of electrons in solids varies by nearly five orders of magnitude (from 0.014 min InSb to over 1000 m e e in heavy fermion compounds), and this variation is determined entirely by thebinding constraint — the band structure — not by the field excitation. The textbook mass meis itself theeffective mass of the vacuum binding, the product of renormalization in quantum electrodynamics, carryingno ontological privilege. The quasiparticle concept in condensed matter physics implicitly acknowledgesthat bound-state entities are distinct constraint patterns. Covalent bonding is better described asreorganization of constraint patterns than as sharing of persistent objects. The persistence illusion — theapparent return of "the same electron" upon re-binding — dissolves once the ontological locus shifts fromthe field excitation to the binding: the same binding always produces the same pattern because the constraintstructure has not changed. This framework dissolves the individuality debate in philosophy of physics,bridges the constraint-based lawhood program with particle metaphysics, and radicalizes ontic structuralrealism by showing that particle types — not just particle individuality — are structure-dependent.
Franny Philos Sophia (Sun,) studied this question.