Exactly :) that is the definition of the uncertainty principle so u got my point, measure one aspect to 100% lose the others, simple.
I´ve set up numerous NMR experiments on this principle. We must measure the quantum spin along one axis forcing it to be zero along the others, and ignoring them, in order to relate the data to anything or even harder, quantify anything.
But the discrepancy in theory vs reality is extremely real and comes from the maths :) they cointain infinite limits etc and has nothing to do with reality!
Even in the most simple solutions of Schrodingers eq in 1D, with the harmonic oscillator model will result in brutal QTE due to these limits :)
Same goes for molecule models, electron dislocation outside molecules, due to the probability wave being outside the molecule in reality but not in theory!
peace
What minimum magnet strength is appropriate for these kinds of NMR experiments?
They are pretty big! I would say 10 T + we got one @ my old uni :) The magnet alone costed way over 1,000,000$
Standard example is the 21 T magnet, would resonate a proton @900 mhz!
And you also need a adiabatic balloon to cool the liquid hydrogen, which cools the circulation of liquid nitrogen which cools the massive magnet temperatures :)