2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/125910Using a novel, non-perturbative, time-dependent string configuration derived in [1], we present here an argument which selects new critical dimensions for the target space time of a bosonic sigma model, with D=4 the lowest non trivial value. This argument is based on the properties of the partition function after a target space Wick rotation.3 pages, LaTeXHigh Energy Physics - TheoryGeneral Relativity and Quantum CosmologyHigh Energy Physics - Phenomenologytext