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Fidelity preserving maps on density operators

Lajos Molnar
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Abstract

We prove that any bijective fidelity preserving transformation on the set of all density operators on a Hilbert space is implemented by an either unitary or antiunitary operator on the underlying Hilbert space.

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BibTeXRIS

Lajos Molnar. 2001-08-08. Fidelity preserving maps on density operators. https://doi.org/10.1016/s0034-4877(01)80091-4

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