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The information entropy of quantum mechanical states (2004)

It is well known that a Shannon based definition of information entropy leads in the classical case to the Boltzmann entropy. It is tempting to regard the Von Neumann entropy as the corresponding quantum mechanical definition. But the latter is problematic from quantum information point of view. Consequently

We introduce a new definition of entropy that reflects the inherent uncertainty of quantum mechanical states.
We derive for it an explicit expression, and discuss some of its general properties.
We distinguish between the minimum uncertainty entropy of pure states, and the excess statistical entropy of mixtures.

$S[\rho]=S_0(N) + F(p_1,p_2,...,p_N) \ne -\sum_r p_r \ln p_r$

[1] A. Stotland, A.A. Pomeransky, E. Bachmat, D. Cohen, Europhysics Letters 67, 700 (2004). [arXiv] [pdf]