Continual Measurements in Quantum Mechanics and Quantum Stochastic Calculus
نویسنده
چکیده
2.1 Quantum stochastic calculus . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 The Fock space . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 The Weyl operators and the Bose fields . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 Quantum stochastic integrals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 2.2 The unitary system–field evolution . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 The Hudson–Parthasarathy equation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 The Hamiltonian evolution . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 2.3 The system–field state . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 2.4 The reduced dynamics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 System observables in the Heisenberg picture . . . . . . . . . . . . . . . . . . . . . . . . 21 The master equation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 2.5 Physical basis of the use of QSC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 The quasi–monochromatic paraxial approximation of the electromagnetic field . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 Approximations in the system–field interaction . . . . . . . . . . . . . . . . . . . . . . 24
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