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A 'simple' Physics postulation...
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TimFox:
Probably (1/137) furlongs
vad:
The answer is: it depends. Depends on the observer’s ability to take velocity measurements.

Imagine that the object (let say a 100kg steel sphere) was thrown up in the air with the initial speed of 1 m/s in complete darkness of the night, and all the observer has is a crappy civil radar with velocity resolution of 1 m/s. To the radar and hence to the observer the object would seem stationary for the most part of its trajectory.

Now imagine another observer, who has the finest laser interferometer and the fastest equipment to measure the smallest wobble of the 100kg sphere at the shortest period of time possible using the current era technology. What would the second observer see when the object reaches the apex? Most likely he/she will observer thermal fluctuations of the ball in the air. The object would never seem stationary to the second observer.

Now imagine another observer - technologically advanced extraterrestrial, who has equipment to take measurements with 10 to -53 power seconds resolution, and freeze the object to the temperatures low enough to rule out thermal jitter. Would the observer be able to dial in timescale resolution in its state-of-the-art measuring equipment and catch the moment when the object is stationary in the apex? The quantum uncertainty principle gives definite “not” as the answer.
dietert1:
You should not write about extraterrestrials when considering a physics question. That's fantasy. As are all answers referring to quantum effects. No healthy scientist will ever apply quantum theory unless necessary. Not even an extraterrestrial physicist..

Regards, Dieter
vad:

--- Quote from: dietert1 on July 10, 2021, 07:08:32 pm ---You should not write about extraterrestrials when considering a physics question. That's fantasy. As are all answers referring to quantum effects. No healthy scientist will ever apply quantum theory unless necessary. Not even an extraterrestrial physicist..

Regards, Dieter

--- End quote ---
There is a Russian saying: “don’t tell me what to do, and I will not tell you where the <censored> you should go”.

Back to physics. The classical mechanics models discussed in this thread have their limits. One limit is thermal fluctuations. Another limit is drawn by quantum mechanics. There is no such thing as exactly zero velocity in the real world
TimFox:
In general, the only things that can be exactly zero are integer variables (e.g., the number of people in the next room or the number of direct flights between Des Moines and Sheboygan today). 
(No--there are no pregnant women in that room.)
However, in mathematics, a continuous variable going from a positive value to a negative value, must pass through zero, even if it does not dwell at zero for a finite time.
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