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arXiv · 2607.02408

Copying Quantum States

Hans Maassen·Burkhard Kümmerer
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Abstract

The no-broadcasting theorem in quantum information says that a set of states on a quantum system admits a common broadcasting (copying) operation if and only if their density matrices belong to a commuting family. We discuss and prove this theorem, as well as the closely related no-cloning theorem in the context of quantum probability theory, i.e. in the category of (finite dimensional) C-star-algebras with unital completely positive maps.

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Hans Maassen, Burkhard Kümmerer. 2026-07-02. Copying Quantum States. https://doi.org/10.1007/s13226-024-00634

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