Predavanja iz Kvantne mehanike

This section introduces fundamental notions of quantum formalism, such as system, state, ensemble, measurement, etc. All these notions are common ingredients of any physical theory, but it turns out that their thorough analysis is not really necessary for classical mechanics. Further, we try to emphasize that these basic notions cannot be introduced independently, i.e. to define one of them the other ones should be also clarified. So, we start with intuitive analysis, being not essentially related to quantum mechanics, in order to single out the main features of the introduced notions. Their rigorous quantum definition will be given in the next section within three postulates, which are also mutually dependent