2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/89007We investigate the issue of speed-up and the necessity of entanglement in Grover's quantum search algorithm. We find that in a pure state implementation of Grover's algorithm entanglement is present even though the initial and target states are product states. In pseudo-pure state implementations, the separability of the states involved defines an entanglement boundary in terms of a bound on the purity parameter. Using this bound we investigate the necessity of entanglement in quantum searching for these pseudo-pure state implementations. If every active molecule involved in the ensemble is `charged for' then in existing machines speed-up without entanglement is not possible.Latex file, no figures, 11 pages, Extended version, To appear in Journal QICQuantum PhysicsSpeed-up and entanglement in quantum searchingtext