On the Limits of Information Retrieval in Quantum Mechanics
Quantum Physics
2013-11-27 v1 Mathematical Physics
math.MP
Abstract
The widely considered assertion is that the unitarity of quantum mechanical evolution assures the preservation of information. It is even promoted in popular literature as an established fact. (Susskind, 2008) Yet, a simple chain of reasoning demonstrates that: 1) almost any evolutionary operator can be well approximated by a degenerate (finite-rank) operator and 2) one needs an eternity to retrieve information exactly from a nonstationary quantum state and to distinguish between arbitrary unitary operator and its finite-dimensional approximations.
Keywords
Cite
@article{arxiv.1311.6781,
title = {On the Limits of Information Retrieval in Quantum Mechanics},
author = {Peter B. Lerner},
journal= {arXiv preprint arXiv:1311.6781},
year = {2013}
}