Arborescent Eternalism: A Variational and Fibered Modal Ontology of Spacetime

This paper introduces Arborescent Eternalism, a framework extending the block universe model by incorporating a structured space of admissible histories. Spacetime is modeled as a fiber bundle in which the realized history emerges as the stationary solution of a variational modal tension functional. The approach explores whether the structured space of admissible trajectories defined by physical law should be treated purely as a mathematical tool or as part of the structural ontology of spacetime.