ABSTRACT
The theory of measurements continuous in time in quantum mechanics (quantum continual measurements) has been formulated by using the notions of instrument and positive operator valued measure [1, 2, 3, 4, 5, 6], arisen inside the operational approach [1, 7] to quantum mechanics, by using functional integrals [8, 9, 10], by using quantum stochastic differential equations [11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23] and by using classical stochastic differential equations (SDE’s) [12, 13, 14, 15, 16, 17, 18, 4, 19, 20, 21, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 6]. Various types of SDE’s are involved, and precisely linear and non linear equations for vectors in Hilbert spaces and for trace-class operators. All such equations contain either a diffusive part, or a jump one, or both.
