Beyond Density Matrices: Geometric Quantum States

Abstract

A quantum system's state is identified with a density matrix. Though their probabilistic interpretation is rooted in ensemble theory, density matrices embody a known shortcoming. They do not completely express an ensemble's physical realization. Conveniently, when working only with the statistical outcomes of projective and positive operator-valued measurements this is not a hindrance. To track ensemble realizations and so remove the shortcoming, we explore geometric quantum states and explain their physical significance. We emphasize two main consequences: one in quantum state manipulation and one in quantum thermodynamics.

7 pages, 1 figure; Supplementary Material: 2 pages; http://csc.ucdavis.edu/~cmg/compmech/pubs/rgqs.htm

References in corpus (3)

• Geometrization of Quantum Mechanics
• Bell inequality violation by entangled single photon states generated from a laser, a LED or a Halogen lamp
• Geometric Quantum Thermodynamics

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