A Measurement in QFT: Mapping Fields to Theory's Math Formalism

[A. Neumaier]

But in your reference I don't see a concrete description of a TPC with the POVM formalism.

This would be a separate paper on its own. I just describe how track measurements actually performed with a TCP (no matter how it is built) can be interpreted as a POVM measurement of position and momentum.

I doubt that my experimental colleagues actually building such instruments use the POVM formalism at all ;-)).

Neither did the spectroscopists before 1925 use the modern quantum formalism.

None of your statements mean that one cannot get correct descriptions in terms of POVMs respective energy levels.

 

[vanhees71]

I don't doubt the POVM formalism in any way. Of course spectroscopists before 1925 didn't use modern quantum formalism. To the contrary before at least 1913 with Bohr's "old quantum mechanics" it was an enigma how to explain the discrete spectra observed by Fraunhofer as well as Kirchhoff and Bunsen in the 19th century. It's only with modern QM that a complete understanding, including intensities, from a generally valid theory has been achieved.