Continuous maximum-entropy inference and open quantum channels

Stephan Weis

Contact the author: Please use for correspondence this email.
Submission date: 23. Feb. 2012 (revised version: July 2012)
Pages: 20
MSC-Numbers: 62F30, 94A17, 94A40
Keywords and phrases: maximum-entropy inference, entropy distance, continuity, open quantum channel
Download full preprint: PDF (513 kB)

Abstract:
We study the continuity of the maximum-entropy inference under linear constraints, for quantum systems modeled on finite-dimensional Hilbert spaces. The von Neumann entropy of the inference depends upper semicontinuously on mean values. Discontinuities of the inference are characterized in terms of an openness condition relating to the linear map that assigns mean values. We also prove sufficient conditions for this openness condition.