Abstract
We show that nonlocality of quantum mechanics cannot lead to superluminal transmission of information, even if most general local operations are allowed, as long as they are linear and trace preserving. In particular, any quantum-mechanical approximate cloning transformation does not allow signaling. On the other hand, the no-signaling constraint on its own is not sufficient to prevent a transformation from surpassing the known cloning bounds. We illustrate these concepts on the basis of some examples.
- Received 11 May 2000
DOI:https://doi.org/10.1103/PhysRevA.62.062302
©2000 American Physical Society