False loss of coherence
Quantum Physics
2011-10-12 v1
Abstract
The loss of coherence of a quantum system coupled to a heat bath as expressed by the reduced density matrix is shown to lead to the miss-characterization of some systems as being incoherent when they are not. The spin boson problem and the harmonic oscillator with massive scalar field heat baths are given as examples of reduced incoherent density matrices which nevertheless still represent perfectly coherent systems.
Cite
@article{arxiv.1110.2199,
title = {False loss of coherence},
author = {William G. Unruh},
journal= {arXiv preprint arXiv:1110.2199},
year = {2011}
}
Comments
18 pages. This paper was published in {\bf Relativistic Quantum Measurement and Decoherence}, ed F. Petruccione, Springer Velag(2000) and is being placed on the arxiv now for future reference and for ease in retrieval