The SV0 principle. A cosmological symmetry origin for visible and dark matter.

The observable universe presents three structural facts that the ΛCDM model treats as independent initial conditions: the absence of macroscopic antimatter, the existence of exactly two material sectors, and the proximity of their energy densities. In this work we propose that these three facts are consequences of the symmetry geometry of a single primordial scalar field. The U(1) symmetry of the primordial field is not an independent postulate. It is the inevitable geometric property of any complex scalar field that persists and evolves in time. From this minimal assumption, the SV0 principle postulates the existence of a conserved cosmological quantity —the SV0 charge— associated with the U(1) phase symmetry of a primordial complex scalar field. The discrete subgroup Z(2) ⊂ U(1), the unique reflection subgroup of U(1), naturally produces a binary partition of the charge space, giving rise to exactly two material sectors. The initial conditions during inflation spontaneously break this Z(2) symmetry, establishing a unique charge sign in the observable universe and eliminating domains of macroscopic antimatter. The distribution of charge between sectors produces comparable number densities, suggesting a dark matter candidate mass in the GeV range. The SV0 principle does not constitute a proof but a proposal for cosmological organization. Its merits reside in the structural unification of phenomena treated separately, in the derivation of the material bipartition as a geometric consequence, and in its falsifiability through independent observational channels. The paper is accompanied by two annexes of explicitly speculative character. They do not form part of the core argument and are presented separately for that reason. Their value does not reside in being correct but in being coherent with the structure of the principle and in opening precise directions that the principle suggests naturally when taken to its deeper consequences. Annex A explores the possibility that dark energy emerges as a remnant of the same primordial field, extending the SV0 principle to the three components of the cosmological landscape. Annex B examines the connection between the Z(2) breaking, the arrow of time, and the question of entropy and existence.