{{eftersyn|dato=december 2015}}
{{Kvantemekanik}}
[[Kvantemekanik]] forudsætter en omhyggelig definition af '''kvantemekanisk måling'''.  Kvantemekanisk måling problemstillingen ligger til grund for [[kvantemekanikfortolkninger]] - og der er i dag (2015) ikke konsensus om kvantemekanisk måling.<ref name="Cresser">[http://physics.mq.edu.au/~jcresser/Phys301/Chapters/Chapter13.pdf J D Cresser 2009, Quantum Physics Notes, Department of Physics Macquarie University: Chapter 13 Observables and Measurements in Quantum Mechanics] Citat: "...One of the most difficult and controversial problems in [[Kvantemekanik|quantum mechanics]] is the so-called measurement problem. Opinions on the significance of this problem vary widely. At one extreme the attitude is that there is in fact no problem at all, while at the other extreme the view is that the measurement problemis one of the great unsolved puzzles of quantum mechanics...Any quantum measurement then appears to require three components: the system, typically a microscopic system, whose properties are to be measured, the measuring apparatus itself, which interacts with the system under observation, and the environment surrounding the apparatus whose presence supplies the [[dekohærens|decoherence]] needed so that, ‘for all practical purposes (FAPP)’, the apparatus behaves like a classical system...This larger system could include, for instance, the measuring apparatus itself, so that instead of making a projective measurement on the system itself, one is made on the measuring apparatus. We will not be discussing these aspects of measurement theory here...", [https://web.archive.org/web/20190321235633/http://physics.mq.edu.au/~jcresser/Phys301/Chapters/Chapter13.pdf backup], [http://physics.mq.edu.au/~jcresser/Phys301/Chapters/ Notekatalog]</ref><ref>[https://arxiv.org/abs/1408.2093 Elliott Tammaro∗ Department of Physics,  Chestnut  Hill College,  Philadelphia,  Pennsylvania,  USA: Why Current Interpretations of Quantum Mechanics are Deficient], [https://arxiv.org/pdf/1408.2093.pdf pdf] Citat: "...Quantum mechanics under the Copenhagen interpretation is one of the most experimentally well verified formalisms. However, it is known that the interpretation makes explicit reference to external observation or “measurement.” One says that the [[Københavnerfortolkningen|Copenhagen interpretation]] suffers from the measurement problem...We argue, and where possible, demonstrate, that all common interpretations have unresolved deficiencies. Among these deficiencies are failures to resolve the measurement problem, fine-tuning problems, logical/mathematical inconsistencies, disagreement with experiment, and others. Short-comings as severe as these call into question the viability of any of the common interpretations. When appropriate, we indicate where future work may resolve some of these issues...At this point in time it appears that a stalemate has been reached with regard to the interpretation of quantum mechanics. Surprisingly, despite the roughly ninety years since its conception, there is currently no single widely accepted interpretation.<br>The variety of interpretations has acted to divide the physics community into camps. For example, one might be a “Bohmian” or an “Everettian” or in the “I shut up and calculate” camp. There is virtually no travel between camps, but there is much in the way of campaigning for new recruits...The decoherence program attempts to bypass the difficulties associated with the Copenhagen interpretation by claiming that while the evolution of a perfectly isolated system is governed by Process 2 alone, no quantum system is truly isolated during the measurement proces...Does decoherence actually solve the preferred basis problem? We will argue that decoherence does not solve preferred basis problem, and more generally, that unitary dynamics alone cannot do so [26]...An essential point is that the system of interest, the measuring apparatus, and the environment must necessarily form a closed system. Well known is that this demands that the evolution of the full system is unitary. Often overlooked, however, especially within the context of measurement problem resolutions, is the fact that closed systems must also conserve energy. Does the decoherence formalism satisfy this well established dictum?  Let us demonstrate that it does not...XI.  CONCLUDING REMARKS We challenge the viability of common interpretations of quantum mechanics. We have argued, and where possible, demonstrated, that each interpretation exhibits significant deficiency, in the form of fine-tuning problems/adhoc assumptions, internal inconsistencies, incompleteness, disagreement with experiment, among others..."</ref>
Fysik Videnskab