2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/114530The quantum dynamics of M pairwise coupled spin 1/2 is analyzed and the time evolution of the entanglement get established within a prefixed couple of spins is studied. A conceptual and quantitative link between the concurrence function and measurable quantities is brought to light providing a physical interpretation for the concurrence itself as well as a way to measure it. A generalized spin star system is exactly investigated showing that the entanglement accompanying its rich dynamics is traceable back to the covariance of appropriate commuting observables of the two spins.7 pages, 3 figures, submitted to Phys Rev BQuantum Physicstext