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At room temperature, air molecules zip around at about kilometres an hour. At about 10 micro degrees Kelvin, Rubidium atoms move at only about 0. But matter cannot reach absolute zero, because of the quantum nature of particles. This has to do with Heisenberg's uncertainty principle we can never know exactly both a particle's speed and position; in fact, the more precisely we know its speed, the less precisely we know its position. If an atom could reach absolute zero, its temperature would be precisely zero, which implies an exact speed of zero.
But knowing the atom's speed exactly, means we know nothing at all about its position. If an atom could attain absolute zero, its wave function would extend "across the universe," which means the atom is located nowhere. But that's an impossibility. When we try to probe the atom or electron to localize it, then we give it some velocity, and thus a non-zero temperature.
By the way, we can think of an atom either as a particle a little billiard ball or as a wave. As atoms come close to absolute zero, their waveforms spread out. Asked 1 year, 9 months ago. Active 1 year, 9 months ago. Viewed 2k times. Improve this question. UM Desai. I don't think so.
So why they write this sh? Add a comment. Active Oldest Votes. Improve this answer. Deschele Schilder Deschele Schilder 1. I'm not sure how this process finds place, but think about it like a Brownian particle.
But hen faster. From here to there, to over there to wherever. If we consider the electron's wavefunction to be spread out all over space. So on average, the electron's position is everywhere but the momentum has a sharp delta distribution peak. Like for instance an excited electron "moving" between two energy levels in an atom.
AFAIK, there is no continuous "between" state, so the electron can't really be said to be moving. And of course part of the foundation of quantum mechanics is that if the electron actually orbited around the nucleus - that is, is moving - it'd be radiating electromagnetic energy.
I've just asked Can elementary particles be nicely classified into "force transmitters" and "force emitters"? States with definite energy turn out not to be changing at all in time, unlike some little particle whizzing around from one place to another.
So perhaps what you're wondering is why the lowest energy state still has kinetic energy, as if the electron were moving, and more potential energy than it would have if the electron were somewhere in the nucleus.
All we can do is refer you to our many other "mediocre" answers on basic quantum mechanics. These objects simply don't have the properties of classical things. Their waves don't have single velocities, but spreads of velocities. They don't have positions, but spreads of positions. The narrower the range of positions, the broader the range of velocities, due to the nature of what wave property corresponds to velocity.
So there's a trade-off.
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