Remote preparation of arbitrary ensembles and quantum bit commitment
Quantum Physics
2007-05-23 v2 Mathematical Physics
math.MP
Operator Algebras
Abstract
The Hughston-Jozsa-Wootters theorem shows that any finite ensemble of quantum states can be prepared "at a distance", and it has been used to demonstrate the insecurity of all bit commitment protocols based on finite quantum systems without superselection rules. In this paper, we prove a generalized HJW theorem for arbitrary ensembles of states on a C*-algebra. We then use this result to demonstrate the insecurity of bit commitment protocols based on infinite quantum systems, and quantum systems with Abelian superselection rules.
Cite
@article{arxiv.quant-ph/0310001,
title = {Remote preparation of arbitrary ensembles and quantum bit commitment},
author = {Hans Halvorson},
journal= {arXiv preprint arXiv:quant-ph/0310001},
year = {2007}
}
Comments
21 pages, LaTeX. Version 2: Proofs expanded and made more self-contained; added an example of a bit commitment protocol with continuous ensembles