I have been told that though glass seems like a solid, it is somehow, in theory, a liquid -- but is just somehow a liquid that is so thick that it appears to be solid. (Of course --- if this premise to my question is an urban myth then let me know, and that will qualify as an answer.)

My question is this ---- by what factor would you have to slow down time if you want regular water to appear as-though solid to you the way glass does?

  • $\begingroup$ This is a philosophical question, but do you mean to say that you slow down time for every part of the system except the observer? If you didn't slow down the observer, the observation would not change. $\endgroup$ – Ian Jun 13 '15 at 19:24
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    $\begingroup$ Glass flows, but it doesn't flow like a liquid, so the time scale argument is only a very crude model for what's going on. What are the differences? For instance, in a real liquid one can cause turbulent motion, but the amount of pressure that would be necessary to cause turbulence in glass, at least theoretically, would not only shatter the glass but probably instantly ionize it into a plasma, so the turbulent state simply doesn't exist. $\endgroup$ – CuriousOne Jun 13 '15 at 19:41
  • $\begingroup$ @Ian - I mean that if you slow down time by a factor of x, that means that the observer experiences x seconds every time a clock in the room would indicate that one second has passed. $\endgroup$ – Sophia_ES Jun 13 '15 at 20:04
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    $\begingroup$ The idea that glass is a liquid is an urban legend. $\endgroup$ – Mike Dunlavey Jun 13 '15 at 20:17
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    $\begingroup$ Related: physics.stackexchange.com/q/65740/2451 and links therein. $\endgroup$ – Qmechanic Jun 13 '15 at 20:40

Contrary to popular misconception, below a specific temperature, glasses do not flow. At all. A glass by definition is a solid sans repeating crystalline structure. Anything which flows (see "pitch-drop experiment which drops every 80 (or something) years") is a liquid, however viscous. Liquid glasses tend to have reasonably high viscosity, but once they freeze, they're solid and do not flow or deform.

So the strict answer to your question about water and time is that you'll need to freeze time to make liquid water behave like solid glass.


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