Postulates of Quantum Mechanics from quantum mechanics by
Postulates of Quantum Mechanics (from “quantum mechanics” by Claude Cohen-Tannoudji) 6 th postulate: The time evolution of the state vector is governed by the Schroedinger equation where H(t) is the observable associated with the total energy of the system. 1 st postulate: At a fixed time t 0, the state of a physical system is defined by specifying a ket
Postulates of Quantum Mechanics (from “quantum mechanics” by Claude Cohen-Tannoudji) 2 nd postulate: Every measurable physical quantity is described by an operator This operator is an observable. 3 rd postulate: The only possible result of the is one of the eigenvalues measurement of a physical quantity of the corresponding observable 4 th postulate (non-degenerate): When the physical quantity is measured on a system in the normalized state obtaining the eigenvalue where the probability of of the corresponding observable is is the normalized eigenvector of associated with the eigenvalue
Physical interpretation of is a probability density. The probability of finding the particle in the volume element at time General solution for Try separation of variables: Plug into TDSE to arrive at the pair of linked equations: and is
Orthogonality: For which are different eigenvectors of we have orthogonality: Let us prove this to introduce the bra/ket notation used in the textbook
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