7 ms·

It's almost like a "standing wave" (of the square pattern) emerged spontaneously out of a chaotic stew of probability waves, and I guess that's a better way to

It's almost like a "standing wave" (of the square pattern) emerged spontaneously out of a chaotic stew of probability waves, and I guess that's a better way to describe quantum mechanics at this level than to say "The Na and Cl atoms snapped together". Nothing snapped to together. This video shows a pattern emerging from pure chaos, all based on probabilities and the fact that each individual atom probability wave can only oscillate in certain patterns. I'm pretty sure in Quantum Mechanics systems like this the entire unit behaves as one and there's no real distinction possible regarding "which is which" if you were to try to identify individual atoms. It would be like looking at a standing wave pattern in water (or any other medium) and labeling one peak "Wave A" and some peak "Wave B". You can't really do it. Because for the standing wave pattern to exist at all it has to be the entire system interaction to cause it to emerge. I'm not saying atoms are "Standing Waves" but I'm merely making an analogy. However even from some perspective you could even say any oscillating system of wave probabilities when taken as a "system" comprises a standing wave.

WClayFerguson 6y ago
Not that I'm trying to blow anyone's mind but here's a couple of other 'emergent patterns' in reality which can also be called standing waves, which proves some very low level patterns like DNA can cause identical patterns to emerge billions of layers higher in the causal chain of reality, and way higher than just the physical structure of the body and brain but also into the surrounding world. https://www.reddit.com/r/BeAmazed/comments/l2mtfx/separated_at_birth/ https://www.reddit.com/r/BeAmazed/comments/l2mtfx/separated_...
gus_massa 6y ago
> I'm pretty sure in Quantum Mechanics systems like this the entire unit behaves as one and there's no real distinction possible regarding "which is which" if you were to try to identify individual atoms. The grow experiment was at room temperature 298K. At this temperature the nuclei of the atoms behave almost classically. There are some important quantum effects between the electrons, but their mass is like 10000 smaller. The effects are small in the electrons in the lower levels that are close to the nuclei, but in the valence band they can be very important. Specially in conductors where the electrons are very delocalized, but this is not a conductor.
- thaumasiotes 6y ago
  > At this temperature the nuclei of the atoms behave almost classically. The video seems to show a crystal made of fairly large spheres... which appear from nothing. I don't see a bunch of chaotic spheres which arrange themselves into a grid; I see a grid of spheres appearing where there was nothing before. I have a hard time thinking this corresponds to classical mechanics. :/
  - tsimionescu 6y ago
    The timescale is relevant. You're seeing 2 frames milliseconds apart of a process that took probably a few nanoseconds.
    - thaumasiotes 6y ago
      Why are there any frames in which the sodium and chlorine atoms appear not to exist? Suppose there was just the chlorine (no sodium), and we observed it the same way. Would we see mostly chaotic arrangements of big spheres, or mostly a smooth background with no spheres?
      - gus_massa 6y ago
        Near the bottom is a figure with some cherry picked frames of the video and a handmade drawing showing the crystal and the incoming pairs of atoms. The Brownian motion depends on the mass of the object, so the average movement of the individual atoms is higher than the average movement of the small crystal. So the isolated atoms are blurred in the image.
        WClayFerguson 6y ago
        I answered all this in my reply to l33tman, above so I won't repeat that here, but check it out.
      - tsimionescu 6y ago
        Because you are seeing frames once every few milliseconds of atoms moving back and forth at speeds a fraction of the speed of light. It's only when they happen to be in very fixed positions that you have any hope to notice a definite image of the NaCl molecule. In general, the very fact that you can see something should be a clear indication that you are not observing quantum behavior: particles whose properties (such as position) are measured DO NOT behave according to classical physics, they no longer display quantum effects. And while we have yet to understand what exactly counts as a measurement, something which allows you to have a picture of the atoms certainly counts.
l33tman 6y ago
There is really nothing quantum in this, you can simulate this completely classically, although it takes forever as it's a slow process, as you seen when you compare the timescale of the video in the seconds to the timescale the atoms move about, in the femtoseconds. I'm not a salt nucleation expert by any means, but I'd imagine the process has a similar statistics as protein folding. Individual folding events (and nucleation events) are superfast but takes forever to trigger (a lot of stars have to align so to speak). This is why, from just looking at frames 1/25s apart, it looks like suddenly things appeared out of nothing, but really there were eons of time in between the frames in the video.
- WClayFerguson 6y ago
  > There is really nothing quantum in this Even if you consider a Hydrogen atom floating in free space a billion miles from any planets, everything about it is 100% "quantum". There are no actual electrons going around the nucleus, because it's purely just a quantum probability wave. If you then introduce Oxygen atoms near it, then the probability wave of the two begin to behave as a single system and will oscillate in a different pattern but STILL a single quantum mechanical system, and one big "wave function" that represents the entire system. In this multi-atom system you also cannot even say that one specific electron is going around one atom, and another electron is going around a different electron (the incorrect classical view). The electron probability wave for the entire system is one big probability wave oscillator function, and both electrons contribute to magnitudes of observables in an identical way to each other. So the two electrons loose their individual identity. They're both part of a 'cloud' but you can't say where any of them are. Not because it's hard to measure, but because actually reality itself doesn't even know. None of this is inconsistent with the fact that the classical view also holds true under ordinary observational conditions, and can be estimated (albeit incorrectly) as pre-existing atoms "snapping together" by the laws of chemistry, but that is the less 'complete' view. Just like Newton is a less complete view than Relativity, but still 'works'.
  - tsimionescu 6y ago
    While the electrons do form a cloud and aren't entirely well positioned in space as far as we know, it's important to remember that there still are a fixed number of electrons which can be detected one by one, even though they may interact with themselves or each other at multiple positions at the same time before our detection. Furthermore, it is not yet proven that reality behaves the same in classical settings as it does in quantum interactions. For all we know, wave function collapse may be a physical phenomenon that happens at specific conditions, yielding purely classical behavior. Your explanation is one popular view of QM, but it is not the only possibility that would be consistent with observations.

WClayFerguson 6y ago

Not that I'm trying to blow anyone's mind but here's a couple of other 'emergent patterns' in reality which can also be called standing waves, which proves some very low level patterns like DNA can cause identical patterns to emerge billions of layers higher in the causal chain of reality, and way higher than just the physical structure of the body and brain but also into the surrounding world. https://www.reddit.com/r/BeAmazed/comments/l2mtfx/separated_at_birth/ https://www.reddit.com/r/BeAmazed/comments/l2mtfx/separated_...

gus_massa 6y ago

> I'm pretty sure in Quantum Mechanics systems like this the entire unit behaves as one and there's no real distinction possible regarding "which is which" if you were to try to identify individual atoms. The grow experiment was at room temperature 298K. At this temperature the nuclei of the atoms behave almost classically. There are some important quantum effects between the electrons, but their mass is like 10000 smaller. The effects are small in the electrons in the lower levels that are close to the nuclei, but in the valence band they can be very important. Specially in conductors where the electrons are very delocalized, but this is not a conductor.

thaumasiotes 6y ago
> At this temperature the nuclei of the atoms behave almost classically. The video seems to show a crystal made of fairly large spheres... which appear from nothing. I don't see a bunch of chaotic spheres which arrange themselves into a grid; I see a grid of spheres appearing where there was nothing before. I have a hard time thinking this corresponds to classical mechanics. :/
- tsimionescu 6y ago
  The timescale is relevant. You're seeing 2 frames milliseconds apart of a process that took probably a few nanoseconds.
  - thaumasiotes 6y ago
    Why are there any frames in which the sodium and chlorine atoms appear not to exist? Suppose there was just the chlorine (no sodium), and we observed it the same way. Would we see mostly chaotic arrangements of big spheres, or mostly a smooth background with no spheres?
    - gus_massa 6y ago
      Near the bottom is a figure with some cherry picked frames of the video and a handmade drawing showing the crystal and the incoming pairs of atoms. The Brownian motion depends on the mass of the object, so the average movement of the individual atoms is higher than the average movement of the small crystal. So the isolated atoms are blurred in the image.
      - WClayFerguson 6y ago
        I answered all this in my reply to l33tman, above so I won't repeat that here, but check it out.
    - tsimionescu 6y ago
      Because you are seeing frames once every few milliseconds of atoms moving back and forth at speeds a fraction of the speed of light. It's only when they happen to be in very fixed positions that you have any hope to notice a definite image of the NaCl molecule. In general, the very fact that you can see something should be a clear indication that you are not observing quantum behavior: particles whose properties (such as position) are measured DO NOT behave according to classical physics, they no longer display quantum effects. And while we have yet to understand what exactly counts as a measurement, something which allows you to have a picture of the atoms certainly counts.

l33tman 6y ago

There is really nothing quantum in this, you can simulate this completely classically, although it takes forever as it's a slow process, as you seen when you compare the timescale of the video in the seconds to the timescale the atoms move about, in the femtoseconds. I'm not a salt nucleation expert by any means, but I'd imagine the process has a similar statistics as protein folding. Individual folding events (and nucleation events) are superfast but takes forever to trigger (a lot of stars have to align so to speak). This is why, from just looking at frames 1/25s apart, it looks like suddenly things appeared out of nothing, but really there were eons of time in between the frames in the video.

WClayFerguson 6y ago
> There is really nothing quantum in this Even if you consider a Hydrogen atom floating in free space a billion miles from any planets, everything about it is 100% "quantum". There are no actual electrons going around the nucleus, because it's purely just a quantum probability wave. If you then introduce Oxygen atoms near it, then the probability wave of the two begin to behave as a single system and will oscillate in a different pattern but STILL a single quantum mechanical system, and one big "wave function" that represents the entire system. In this multi-atom system you also cannot even say that one specific electron is going around one atom, and another electron is going around a different electron (the incorrect classical view). The electron probability wave for the entire system is one big probability wave oscillator function, and both electrons contribute to magnitudes of observables in an identical way to each other. So the two electrons loose their individual identity. They're both part of a 'cloud' but you can't say where any of them are. Not because it's hard to measure, but because actually reality itself doesn't even know. None of this is inconsistent with the fact that the classical view also holds true under ordinary observational conditions, and can be estimated (albeit incorrectly) as pre-existing atoms "snapping together" by the laws of chemistry, but that is the less 'complete' view. Just like Newton is a less complete view than Relativity, but still 'works'.
- tsimionescu 6y ago
  While the electrons do form a cloud and aren't entirely well positioned in space as far as we know, it's important to remember that there still are a fixed number of electrons which can be detected one by one, even though they may interact with themselves or each other at multiple positions at the same time before our detection. Furthermore, it is not yet proven that reality behaves the same in classical settings as it does in quantum interactions. For all we know, wave function collapse may be a physical phenomenon that happens at specific conditions, yielding purely classical behavior. Your explanation is one popular view of QM, but it is not the only possibility that would be consistent with observations.