Algebraic Quantum Theory of the Josephson Microwave Radiator

Gerisch, T.; Honegger, Reinhard; Rieckers, Alfred

doi:10.1007/s00023-003-0155-3

Cited by 1 publication

(1 citation statement)

References 57 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…289 Realistic models have been studied in the context of both the C * -algebraic and the von Neumann algebraic approach by Rieckers and his associates. See, for example, Honegger & Rieckers (1994), Gerisch, Münzner, & Rieckers (1999, Gerisch, Honegger, & Rieckers (2003), and many other papers. For altogether different approaches to macroscopic observables see van Kampen (1954Kampen ( , 1988Kampen ( , 1993, Wan & Fountain (1998), Harrison & Wan (1997), ), Fröhlich, Tsai, & Yau (2002, and Poulin (2004).…”

Section: Poisson Structure and Dynamicsmentioning

confidence: 99%

Between Classical and Quantum

Landsman¹

2007

Philosophy of Physics

106

140

View full text Add to dashboard Cite

The relationship between classical and quantum theory is of central importance to the philosophy of physics, and any interpretation of quantum mechanics has to clarify it. Our discussion of this relationship is partly historical and conceptual, but mostly technical and mathematically rigorous, including over 500 references. For example, we sketch how certain intuitive ideas of the founders of quantum theory have fared in the light of current mathematical knowledge. One such idea that has certainly stood the test of time is Heisenberg's 'quantum-theoretical Umdeutung (reinterpretation) of classical observables', which lies at the basis of quantization theory. Similarly, Bohr's correspondence principle (in somewhat revised form) and Schrödinger's wave packets (or coherent states) continue to be of great importance in understanding classical behaviour from quantum mechanics. On the other hand, no consensus has been reached on the Copenhagen Interpretation, but in view of the parodies of it one typically finds in the literature we describe it in detail.On the assumption that quantum mechanics is universal and complete, we discuss three ways in which classical physics has so far been believed to emerge from quantum physics, namely in the limit → 0 of small Planck's constant (in a finite system), in the limit N → ∞ of a large system with N degrees of freedom (at fixed ), and through decoherence and consistent histories. The first limit is closely related to modern quantization theory and microlocal analysis, whereas the second involves methods of C * -algebras and the concepts of superselection sectors and macroscopic observables. In these limits, the classical world does not emerge as a sharply defined objective reality, but rather as an approximate appearance relative to certain "classical" states and observables. Decoherence subsequently clarifies the role of such states, in that they are "einselected", i.e. robust against coupling to the environment. Furthermore, the nature of classical observables is elucidated by the fact that they typically define (approximately) consistent sets of histories.This combination of ideas and techniques does not quite resolve the measurement problem, but it does make the point that classicality results from the elimination of certain states and observables from quantum theory. Thus the classical world is not created by observation (as Heisenberg once claimed), but rather by the lack of it.

show abstract