Timeline for Why don't marbles naturally arrange themselves like a crystal?
Current License: CC BY-SA 4.0
12 events
| when toggle format | what | by | license | comment | |
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| Nov 25, 2018 at 19:18 | comment | added | user137289 | The interaction potentials in that paper are Coulomb and hard spheres. Yes, spheres are hard because of Pauli exclusion, but otherwise that interaction is really classical. | |
| Nov 25, 2018 at 19:02 | comment | added | anna v | @Pieter web.science.uu.nl/SCM/Articles/2003/Yethiraj_Nature_2003.pdf this one is talking of an der Waals and interaction potentials, how can qm be absent from the model.. a number of articles come up, but I am not willing to pursue it. In any case classical emerges from quantum, the questions is whether quantum effects persist. | |
| Nov 25, 2018 at 18:40 | comment | added | user137289 | @annav That quote was about the size-dependent colors of nanocrystals, about the electron states in tiny crystals of semiconductors (also in red gold colloids in glass), less than about 30 nm. It does not effect the larger-scale of ordering. | |
| Nov 25, 2018 at 18:12 | comment | added | anna v | @Pieter " Concerning their physicochemical properties, colloids cannot be consistently described if understood only as solid-state matter. They are subject to the "quantum size effect", which renders classical physics inappropriate and makes aspects of quantum mechanics neccessary to describe these particles." nanolytics.de/en/nanolytics/why_colloids . | |
| Nov 25, 2018 at 17:08 | comment | added | user137289 | @annav No, colloids do not involve quantum mechanics. There are repulsive Coulomb forces because the particles often have a surface charge. Together with confinement, this is probably enough to explain long-range ordering (I do not know much about colloids either). | |
| Nov 25, 2018 at 17:00 | comment | added | Alchimista | And yes your answer is the correct one if tgere is confinement or pressure is applied. I even do not see anything special anymore :) | |
| Nov 25, 2018 at 12:56 | comment | added | Alchimista | Point is what is driving organization. It seems that confinement is needed (the container) so that a push is basically acting as a binding force) | |
| Nov 25, 2018 at 12:53 | comment | added | Alchimista | Ory isn't at play. The fact is that I find all A reasonable as we are at two different levels. One is merely topological and statistical and one as in crystals including strong interaction. Apparently non binding hs are not at equipotential even in the same gravitational potential. I did ask @GiorgioP for a hint in how to see that. | |
| Nov 25, 2018 at 12:47 | comment | added | Alchimista | @anna v no is not that molecular level but it doesn't mean that quantum the | |
| Nov 25, 2018 at 12:12 | comment | added | anna v | @Pieter I note the "colloid" , is not that molecular binding levels? i.e. quantum mechanics? You can also make structures with LEGO. | |
| Nov 25, 2018 at 9:57 | comment | added | user137289 | No, it is not really quantum mechanical. One can make crystals of colloid spheres. Opals are a natural example. | |
| Nov 25, 2018 at 8:38 | history | answered | anna v | CC BY-SA 4.0 |