Bipartite subspaces having no LOCC-distinguishable bases
arXiv:quant-ph/0503092 · doi:10.1103/PhysRevLett.95.080505
Abstract
It is proved that there exist subspaces of bipartite tensor product spaces that have no orthonormal bases that can be perfectly distinguished by means of LOCC protocols. A corollary of this fact is that there exist quantum channels having sub-optimal classical capacity even when the receiver may communicate classically with a third party that represents the channel's environment.
12 pages. Two references added in version 2