The postulates of quantum mechanics include: (1) Schrodinger's equation describes how the wave function of a system changes over time, and appears to make the wave function continuous over time. (2) When a measurement is made of quantity m, the wave function instantly changes to an eigenvector of the corresponding operator M. It seems that such a change would most likely be discontinuous in time. It seems as though 2 contradicts 1, unless 1 were stated differently, eg 'Schrodinger's equation describes how a wave function changes over time, between observations'. But the presentations of the postulates I have read don't state it that way, unless I missed it. How can Schrodinger's equation be reconciled with wave function collapse? Thanks for any answers!