What’s the underlying principle on why you can’t know the position and momentum of a particle at the same time? Is there an explanation? I don’t have any knowledge of calculus or the math behind anything so I’m asking here, thanks!
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It has to do with wave particle duality. In reality, all matter (and photons) are both a wave and a particle at the same time. In quantum physics, you use a wave function to define a particle, which is basically a graph of the probability a particle is in a given space at a given time. Now, when an observation is made of a particle, its wave function collapses down to a very small space where that particle can be, but you have no idea where that particle was in it’s wave function a moment ago, so it may have needed to move very far in a very short time, or maybe it only needed to move a little bit to get there, but you can’t know where it was previously without having collapsed the wave function earlier, which would change your later observation. (Note: and observation can be any sort of interation the particle takes, not necessarily a measurement) I cant really think of a good analogy for a certainty momentum, but I can tell you about an experiment. When you cool helium down to very near absolute zero (ie the momentum gets very close to 0) it will actually leak out of whatever container it’s in. That’s because the position becomes less certain than the size of of the container and it can quantum tunnel through the walls of the container. Sorry that second part isn’t really an explanation why, but I did my best. Fun fact: the uncertainty principle also works with energy and time. The more certain we know a particle’s energy state, the less certain we are about how long it will last in that state and vice versa.
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