2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/196104Within the framework of a model universe with time variable space dimension (TVSD), known as decrumpling or TVSD model, we study the time variation of the fine structure constant. Using observational bounds on the present time variation of the fine structure constant, we are able to obtain the present time variation of spatial dimensions.10 pages, accepted for publication in Int.J.Mod.Phys.DHigh Energy Physics - Theorytext