The Breathing Universe: 206_Coherence Domains and the Ontology of Multiplicity in the Breathing Universe

This paper develops a precise ontological treatment of multiplicity within the Breathing Universe Model (BUM) by introducing the concept of coherence domains. In contrast to multiverse or branching interpretations, multiplicity in the BUM does not arise from the coexistence of multiple realized worlds, but from pre-ontological regimes in which coherence has not yet been completed. We formalize coherence completion as a necessary and sufficient condition for the existence of a determinate universe. Before completion, the vacuum exists in a state of structural indeterminacy without observers, histories, or branching alternatives. After completion, coherence is globally fixed, yielding exactly one realized universe with a unique causal history. Under these conditions, ontological branching is shown to be impossible. Coherence domains are defined as transient, pre-completion regions of partial alignment in the vacuum tension field. They allow for local variation, proto-structure, and apparent multiplicity without implying parallel worlds or many-world realizations. Once coherence is completed, these domains collapse into a single consistent ontological outcome. The paper demonstrates that all viable forms of multiplicity compatible with the BUM reduce to a finite set of coherence-domain scenarios, and that any interpretation requiring post-completion branching is incompatible with the model’s foundational constraints. This framework resolves apparent tensions between quantum indeterminacy, cosmological uniqueness, and observer consistency, while preserving empirical continuity with standard physics. The resulting ontology replaces multiverse speculation with a coherence-based account of emergence, showing that multiplicity belongs to the process of becoming, not to the structure of realized reality.