Cavitation of Matter in the Universe into a Degenerated Voronoi Foam

Abstract

Fluids suspended in expanding laboratory systems cavitate into Voronoi foams that degenerate through secondary cavitation of the foam walls. This robust morphological mechanism results from a virtual competition for space between the cavities. In cosmology, Voronoi foams are known to explain important features of the large scale structure, but the physical mechanism for the formation of such foams is unknown. We here present a scenario for the formation of large scale structure: Cavitation initiates at the abrupt reduction of radiation pressure on matter at decoupling and results in the cold flow of matter into a single, void-dominated structure with a scale determined by the Hubble sphere at decoupling. This mechanism does not impose restrictions on the smoothness of the last scattering surface at decoupling and conserves the entropy of matter during the self-organization of a single cavitation foam spanning the observable universe.