Deformed Two-Photon Squeezed States in Noncommutative Space

Recent studies on non-perturbation aspects of noncommutative quantum mechanics explored a new type of boson commutation relations at the deformed level, described by deformed annihilation-creation operators in noncommutative space. This correlated boson commutator correlates different degrees of freedom, and shows an essential influence on dynamics. This paper devotes to the development of formalism of deformed two-photon squeezed states in noncommutative space. General representations of deformed annihilation-creation operators and the consistency condition for the electromagnetic wave with a single mode of frequency in NC space are obtained. Two-photon squeezed states are studied. One finds that variances of the dimensionless hermitian quadratures of the annihilation operator in one degree of freedom include variances in the other degree of freedom. Such correlations show the new feature of spatial noncommutativity and allow a deeper understanding of the correlated boson commutator.Comment: 11 pages. Physics Letters B (accepted

Die längsten Titel der Filmgeschichte : eine Liste

Eine Suche nach den längsten Titeln der Filmgeschichte erweist sich als recht mühsame Sammeltätigkeit. Ohne Hinweise von Freunden wäre vieles hier nicht genannt worden. Dank gilt Caroline Amann, Britta Hartmann, Tobias Sunderdiek, Bodo Traber und Hans J. Wulff. Es sei an alle Leser die Bitte ausgesprochen, fehlende Titel an uns weiterzumelden

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Towns and cities existed throughout Africa’s past. However since the late twentieth century Africans are witnessing a historically unprecedented transition from living mainly in rural areas to residing in cities. What are the driving-forces behind African urbanization? And what are the welfare consequences of rapid urban growth without sufficient economic growth in Africa