2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/41425Recent results on neutrinoless double beta decay, as reported by Klapdor-Kleingrothaus et al., take us for the first time into the realm of Majorana spacetime structure. However, this structure has either been treated as an afterthought to the Dirac construct; or, when it has been attended to in its own right, its physical and mathematical content was never fully unearthed. In this Letter,we undertake to remedy the existing situation. We present a detailed formalism required for the description of the non-trivial spacetime structure underlying the "nu-nubar" metamorphosis - where "nu" generically represents a massive Majorana neutrino, or a massive gaugino.Updated authorship. No other changesHigh Energy Physics - PhenomenologyHigh Energy Physics - TheoryNuclear TheoryParticle-Antiparticle Metamorphosis of Massive Majorana Neutrinos and Gauginostext