Self similarity of the expanding universe as understood by quantum-phase-fields

An idea of the universe as a self-contained system of interacting fields as a closed doublon network is developed. The characteristic scale of this system is considered emergent from general principles. Self similarity of patterns in the universe can be understood by introducing a characteristic scale with respect towhich patterns are evaluated. The developed physical-mathematical model is in good agreement with cosmological length scales and gives a rationale of the empirical fact for an expanding universe. Within the framework of the de~Broglie-Bohm double solution program, the model can be applied to rationalize the existence of a ground potential and a cosmological constant.