2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/34367If there is a shortest length in nature, for example at the Planck scale of 10^-35m, then the cosmic expansion should continually create new comoving modes. A priori, each of the new modes comes with its own vacuum energy, which could contribute to the cosmological constant. I discuss possible mathematical models for a shortest length and an explicit model for a corresponding mode-generating mechanism.5 pages, LaTeX, Proceedings 18th IAP Colloquium, Paris July 1-5, 2002General Relativity and Quantum CosmologyHigh Energy Physics - Theorytext