ua nt - p h / 01 05 03 6 v 1 9 M ay 2 00 1 ARE NUMBER AND PHASE COMPLEMENTARY OBSERVABLES ?
نویسنده
چکیده
The aim of this paper is to clarify the sense in which number and phase in quantum optics can be described as complementary observables. Here phase observables are characterised as phase shift covariant positive operator measures, with the number operator playing the part of the shift generator. Let H be a complex separable Hilbert space, (| n〉)n≥0 an orthonormal basis, and N = ∞ n=0 n|n 〉〈n| the associated number observable with the domain D(N) = {φ ∈ H | ∑
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