The Wigner-Yanase entropy is not subadditive
Mathematical Physics
2007-05-23 v2 math.MP
Abstract
Wigner and Yanase introduced in 1963 the Wigner-Yanase entropy defined as minus the skew information of a state with respect to a conserved observable. They proved that the Wigner-Yanase entropy is a concave function in the state and conjectured that it is subadditive with respect to the aggregation of possibly interacting subsystems. While this turned out to be true for the quantum-mechanical entropy, we negate the conjecture for the Wigner-Yanase entropy by providing a counter example.
Cite
@article{arxiv.math-ph/0609019,
title = {The Wigner-Yanase entropy is not subadditive},
author = {Frank Hansen},
journal= {arXiv preprint arXiv:math-ph/0609019},
year = {2007}
}
Comments
To appear in Journal of Statistical Physics