Meaning of the density matrix

Authors
Anandan, J Aharonov, Y
Citation
J. Anandan et Y. Aharonov, Meaning of the density matrix, FOUND PH L, 12(6), 1999, pp. 571-578
Citations number
3
Categorie Soggetti
Physics
Journal title
FOUNDATIONS OF PHYSICS LETTERS
ISSN journal
08949875 → ACNP
Volume
12
Issue
6
Year of publication
1999
Pages
571 - 578
Database
ISI
SICI code
0894-9875(199912)12:6<571:MOTDM>2.0.ZU;2-F
Abstract
Protective measurement, which was proposed as a method of observing the wav efunction of a single system, is extended to the observation of the density matrix of a single system. This provides a new meaning to the density matr ix as having the same ontological status as the wavefunction describing a p ure state. This also enables quantum entropy to be associated with a single system.