Dilation Theoretic Parametrizations of Positive Matrices with Applications to Quantum Information
نویسنده
چکیده
Abstract. In this note, dedicated to the memory of Professor Tiberiu Constantinescu, we discuss the applications of two parametrizations of positive matrices to issues in quantum information theory. The first, which we propose be dubbed the Schur-Constantinescu parametrization, is used in a twin fashion to construct examples of separable states in arbitrary dimensions. The second, called the Jacobi parametrization, is used to describe quantum states in dimension two, as an alternative to the Bloch sphere representation.
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