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Regarding this question: Would a cup of a superhydrophobic material ever fill with water?

I am completely baffled by the reason for the closure. "Not mainstream physics"?

The question as posed asks the reader to assume a perfectly hydrophobic material: this is not different from other idealized models in physics, such as an "ideal gas", or "rigid body" or "point particle". Everything else in the question is completely standard statistical thermodynamics + fluid mechanics + surface science.

Is the idealized material the problem or something else?

The material is assumed as a thought experiment as the question says right at the beginning; it can't be non-standard physics because I don't claim it actually exists. This assumption is only meant to simplify the analysis of the problem, but in fact there are materials which come pretty close to that behavior, with water contact angles > 170 degrees. So it is not very much of a stretch from real behavior.

Please tell me how the question needs to be modified so it can be reopened.

P.S. Just for fun: water droplet on a surface, from https://link.springer.com/article/10.1007/s10971-018-4825-5

enter image description here

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Statements like “ What would really happen in this scenario? Can you please critique the above reasoning?” are killers.

  1. This is not a site for peer-review of ideas,
  2. Moreover, the suggestion that some really happens is vague. really happens as opposed to what? Virtually happens?

Finally, you make so many assumptions. “only (very short range) repulsive interactions”: how is this even possible? Would the constituents not just spread out in shapeless pieces? You want to assume it’s a cylinder but why is this even reasonable?

Your question assumes a near-impossibility, or at least the question does not propose anything to make your assumptions viable prima faciae.

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  • $\begingroup$ Thanks for explaining. I see perhaps my wording wasn't the clearest, let me try to clarify. "“only (very short range) repulsive interactions”: how is this even possible?" - I mean between it and water, not between it and itself! In the same way that teflon-water interactions are much weaker than water-water or teflon-teflon. Considering the walls of the cup as a continuum solid which doesn't have either dielectric polarizability or dispersion is a simplified model of that $\endgroup$
    – Alex I
    Commented Jul 24 at 1:51
  • $\begingroup$ "really happens as opposed to what? Virtually happens?" - I meant "is my reasoning about this correct". Many questions simply ask a question, in this case I did my best to attempt to work out the answer as well, which shouldn't be a negative $\endgroup$
    – Alex I
    Commented Jul 24 at 1:53
  • $\begingroup$ "This is not a site for peer-review of ideas" - okay, but that's a reason other than "non-standard physics". If that was the main reason, I could simply change the question to "What would happen in this system and why" (removing all my ideas about it) and it would pass, no? $\endgroup$
    – Alex I
    Commented Jul 24 at 1:54
  • $\begingroup$ Last comment ;) Could you please try to answer "How do I need to change this question so it can be reopened?". I appreciate your response but I'm not very much closer to a useful revision of my question after reading it $\endgroup$
    – Alex I
    Commented Jul 24 at 1:56
  • $\begingroup$ granted I probably would not have closed this as “non-mainstream” although the large number of pretty fanciful approximation make your question unrealistic, but I would probably have voted to close as “unclear”. Pick your poison really: “non-mainstream” is sometimes used as a synonym of unrealistic. $\endgroup$
    – ZeroTheHero
    Commented Jul 24 at 3:18
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    $\begingroup$ Honestly I really don’t know what to suggest to reopen this. I would start with reformatting the question, removing the “is my work right” type of statements, and then maybe make an argument that a cylindrical object made from constituents subject to repulsive-only forces is possible (??). With so many assumptions maybe angels can remove the water as it accumulates… $\endgroup$
    – ZeroTheHero
    Commented Jul 24 at 3:21

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