Endomorphisms and Quantum Operations
نویسنده
چکیده
We define a quantum operation as a special type of endomorphism between spaces of matrices. Representations of endomorphisms are considered and an isomorphism between higher dimensional matrices and endomorphisms is derived. We then employ this isomorphism to prove various results for endomorphisms and quantum operations. For example, an endomorphism is completely positive if and only if its corresponding matrix is positive. Although a few new results are proved, this is primarily a survey article that simplifies and unifies previous work on the subject.
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