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sophiecentaur
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. . . . plus a number of other similar comments. But this is not true.The information that can be gleaned from an observation is always subject to Noise. The more 'instantaneous' the measurement, the wider the bandwidth of the measuring instrument and so the more noise energy will affect the result. So a 'good' instantaneous measurement is progressively harder and harder to achieve.russ_watters said:No, radar guns measure speed from doppler shift of reflected radio waves. They are single-point/instantaneous measurements.
We initially learned our Differential Calculus in the ivory tower of Pure Mathematics (even if we didn't know it). Later, if we were lucky, we found that the basics of taking limiting cases of smaller and smaller intervals had to involve caveats about a function being continuous and differentiable before the simple dy/dx can be looked on as valid. QM excludes this condition so we are left with a system that just works but don't look too hard at it.
This thread has a parallel in all the other threads that deal with Zeno's Paradox etc.. Only Professors of Very Hard Sums are qualified to deal with the bottom line of this and many of those guys can't find their back pocket with both hands.