Copying Quantum States

• URL: http://arxiv.org/abs/2607.02408v1
• Date: Thu, 02 Jul 2026 16:40:15 GMT
• Title: Copying Quantum States
• Abstract summary: We discuss and prove the no-broadcasting theorem in quantum information.<n>We also prove the closely related no-cloning theorem in the context of quantum probability theory.
• Score: 0.0
• License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
• 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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