479 research outputs found
Classical mechanics is not h=0 limit of quantum mechanics
Both the set of quantum states and the set of classical states described by
symplectic tomographic probability distributions (tomograms) are studied. It is
shown that the sets have common part but there exist tomograms of classical
states which are not admissible in quantum mechanics and vica versa, there
exist tomograms of quantum states which are not admissible in classical
mechanics. Role of different transformations of reference frames in phase space
of classical and quantum systems (scaling and rotation) determining the
admissibility of the tomograms as well as the role of quantum uncertainty
relations is elucidated. Union of all admissible tomograms of both quantum and
classical states is discussed in context of interaction of quantum and
classical systems. Negative probabilities in classical mechanics and in quantum
mechanics corresponding to the tomograms of classical states and quantum states
are compared with properties of nonpositive and nonnegative density operators,
respectively.Comment: 14 pages, to appear in Journal of Russian Laser Res.(Kluwer Pub.
Probability Distributions and Hilbert Spaces: Quantum and Classical Systems
We use the fact that some linear Hamiltonian systems can be considered as
``finite level'' quantum systems, and the description of quantum mechanics in
terms of probabilities, to associate probability distributions with this
particular class of linear Hamiltonian systems.Comment: LATEX,13pages,accepted by Physica Scripta (1999
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