In quantum statistical mechanics, von Neumann entropy, named after John von Neumann, is the extension of classical entropy concepts to the field of quantum mechanics. For a quantum-mechanical system described by a density matrix ρ, the von Neumann entropy is
where tr denotes the trace. If ρ is written in terms of its eigenvectors |1〉, |2〉, |3〉, ... as
then the von Neumann entropy is
In this form, S can be seen to be related to the Shannon entropy.
Other articles related to "von neumann entropy, entropy, von neumann":
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... state that may be converted into a maximally entangled state is equal to the von Neumann entropy S(p) of the state, which is an extension of the concept of classical ... Mathematically, for a given density matrix p, the von Neumann entropy S(p) is ... Entanglement can then be quantified as the entropy of entanglement, which is the von Neumann entropy of either or as Which ranges from 0 for a ...
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