Isometries of quantum states. (English) Zbl 1047.81017

Summary: This paper treats the isometries of metric spaces of quantum states. In fact, we consider two metrics on the set of all quantum states, namely the Bures metric and that which comes from the trace-norm. We describe all the corresponding (nonlinear) isometries and also present similar results concerning the space of all (non-normalized) density operators.


81P99 Foundations, quantum information and its processing, quantum axioms, and philosophy
47B49 Transformers, preservers (linear operators on spaces of linear operators)
47N50 Applications of operator theory in the physical sciences
81P68 Quantum computation
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