The SV0 principle. A different symmetry breaking and its cosmological consequences

Abstract. This work originates from a single, unpretentious question: what if the fundamental duality of the universe were not matter against antimatter, but visible matter alongside dark matter? Everything that follows is the natural and unforced unfolding of that question. It proposes a unified conceptual framework that simultaneously addresses two sets of open problems in contemporary physics: the interpretive paradoxes of quantum mechanics and the structural mysteries of the standard cosmological model ΛCDM. The starting point is a constitutive definition of the physical domain derived from the practice of physics itself: only the dynamic is physical, where dynamic means that in which process, difference and time are simultaneously operative. From this definition follows an ontological boundary between the physical domain — structured by spacetime, matter and gravity — and a pre-physical domain lacking those categories, which acts as the condition of possibility of the regularities that quantum mechanics describes. The quantum paradoxes — non-locality, superposition, the measurement problem — are recontextualised as category errors: consequences of projecting physical categories onto a domain where they do not operate. On this philosophical foundation the SV0 principle is built: the proposal that there exists a conserved cosmological charge associated with the U(1) symmetry of a primordial complex scalar field, whose reflection subgroup Z(2) ⊂ U(1) generates the bipartition of the material content of the universe into exactly two sectors. From this single conceptual displacement, seven structural facts that ΛCDM accepts as raw data emerge without independent initial conditions: the absence of macroscopic antimatter, the existence of exactly two material sectors, the proximity of their densities, the nature of dark matter, the nature of dark energy, the primordial low-entropy state and the arrow of time. Additionally, the 10¹²⁰ mismatch between the predicted quantum vacuum energy and the observed cosmological constant is reinterpreted as a category error — a comparison between quantities from incommensurable domains — which dissolves upon accepting the ontological boundary. The work does not offer formal demonstrations but an organising principle: a simpler map of known phenomena that, in explanatory parity with the alternatives, wins by economy of assumptions. 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.