Copying Quantum States
arXiv:2607.02408 · doi:10.1007/S13226-024-00634
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.
15 pages, appeared in the Indian Journal of Pure and Applied Mathematics (2024), a vulume dedicated to the memory of K.R. Parthasarathy