Premium
Some Remarks on Unsharp Quantum Measurements, Quantum Non‐Demolition, and All That
Author(s) -
Busch Paul,
Lahti Pekka J.
Publication year - 1990
Publication title -
annalen der physik
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.009
H-Index - 68
eISSN - 1521-3889
pISSN - 0003-3804
DOI - 10.1002/andp.19905020502
Subject(s) - generalization , quantum , demolition , harmonic oscillator , observable , quantum mechanics , physics , von neumann architecture , statistical physics , theoretical physics , mathematics , mathematical analysis , pure mathematics , civil engineering , engineering
The theory of unsharp quantum measurements is reviewed as a generalization of the von Neumann‐Lüders measurement theory and applied to measurements of continuous quantities. A generalized notion of repeatability is proposed which is applicable even to intrinsically unsharp continuous observables. As an illustration a precise formulation of a quantum non‐demolition (QND) measurement performed on a harmonic oscillator is given.