Asymptotic Attainment for Quantum Relative Entropy
Masahito Hayashi
Abstract
In this paper it was proved that the quantum relative entropy D(k) can be asymptotically attained by Kullback Leibler divergences of probabilities given by a certain sequence of measurements. The sequence of measurements depends on , but is independent of the choice of . In classical statistical theory the relative entropy D(pkq) is an information quantity which means the statistical eÆciency in order to distinguish a probability measure p of a measurable space from another probability measure q of the same measurable space. The states correspond to measures on measurable space. When p; q are discrete probabilities, the relative entropy (called also information divergence) introduced by Kullback and Leibler is dened by [1]: D(pkq) := X i p i log p i q i : In general, when p; q are measures on measurable space the relative entropy is dened by: D(pkq) := Z log dq dp (!)p( d!); where dq dp (!) is Radon-Nikodym derivative of q with respect to p. In this paper, we co...