2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/99121The question of finding a lower bound on the number of Toffoli gates in a classical reversible circuit is addressed. A method based on quantum information concepts is proposed. The method involves solely concepts from quantum information - there is no need for an actual physical quantum computer. The method is illustrated on the example of classical Shannon data compression.4 pages, 2 figures; revised versionQuantum Physicstext