Conservation laws, uncertainty relations, and quantum limits of measurements
Quantum Physics
2009-11-07 v1
Abstract
The uncertainty relation between the noise operator and the conserved quantity leads to a bound for the accuracy of general measurements. The bound extends the assertion by Wigner, Araki, and Yanase that conservation laws limit the accuracy of ``repeatable'', or ``nondisturbing'', measurements to general measurements, and improves the one previously obtained by Yanase for spin measurements. The bound also sets an obstacle to making a small quantum computer.
Keywords
Cite
@article{arxiv.quant-ph/0112154,
title = {Conservation laws, uncertainty relations, and quantum limits of measurements},
author = {Masanao Ozawa},
journal= {arXiv preprint arXiv:quant-ph/0112154},
year = {2009}
}
Comments
4 pages, RevTex, to appear in PRL