Distributed compression of quantum information - Dominic Berry

In the usual form of quantum compression, an ensemble of pure states may be compressed to a lower average dimension. In distributed compression, the states are shared between two parties, and the compression must be performed using only local operations. In general, the compression is not as efficient in this case. In the case that the states are orthogonal product states, the compression can take full advantage of correlations between the sources, and the compression is as efficient as global compression. I will show that if the states are nonorthogonal, the compression that is possible is poorer, and no advantage can be gained from correlations between the sources.