2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/184740W. Pauli pointed out that the existence of a self-adjoint time operator is incompatible with the semibounded character of the Hamiltonian spectrum. As a result, people have been arguing a lot about the time-energy uncertainty relation and other related issues. In this article, we show in details that Pauli's definition of time operator is erroneous in several respects.20 pagesQuantum Physicstext