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In this book, we focus our attention on the study of general quantum correlations in both closed and open quantum systems. Our objective is showing their relevance for a thorough understanding of the quantum information processing and of the underlying dynamical processes. In this context, we investigated comparatively their behavior for Greenberger-Horne-Zeilinger (GHZ)-type squeezed states. Moreover, we processed the environmental eects on their dynamics in the case of Bell diagonal states. On the other hand, in the same direction, we borrowed the Wigner function from quantum optics to address its pertinence in detecting and quantifying these correlations. In this respect, by using the negativity of Wigner function we studied the quantum correlations that are present in Werner states made of continuous variables bipartite states (squeezed states and coherent states). We deem that the study performed in this book does represent a major step forward in understanding the quantum correlations, quantum entanglement and quantum discord, the associated properties and their behavior in continuous variable mixed states.

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Fatima-Zahra Siyouri, doctor and researcher in physics at laboratory of theoretical physics, faculty of sciences-Rabat, Mohammed V University.

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