2004/10/31 by E. Shmaya · 4 citations
Physics and Astronomy · #quant-ph
paper · pdf · doi:10.1088/0305-4470/38/44/008
published as J. Phys. A: Math. Gen. 38 (2005) 9717-9727 · 12 pages. Substantial changes. Accepted for publication in Journal of Physics A
arxiv created 2005/09/27 · arxiv updated 2016/09/08
A theorem of Blackwell about comparison between information structures in classical statistics is given an analogue in the quantum probabilistic setup. The theorem provides an operational interpretation for trace-preserving completely positive maps, which are the natural quantum analogue of classical stochastic maps. The proof of the theorem relies on the separation theorem for convex sets and on quantum teleportation.