• Muehe@lemmy.ml
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    9 months ago

    Glass is actually more of a very slow moving liquid than a solid. You can see this on windows that are hundreds of years old, e.g. in churches. They will be thicker on the bottom because part of the glass flowed down.

      • Muehe@lemmy.ml
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        9 months ago

        It’s a matter of debate, but it definitely isn’t a solid.

        A more elaborate alternative definition is this: “Glass is a non-equilibrium, non-crystalline condensed state of matter that exhibits a glass transition. The structure of glasses is similar to that of their parent supercooled liquids (SCL), and they spontaneously relax toward the SCL state. Their ultimate fate, in the limit of infinite time, is to crystallize.” […]

        “On the other hand, any positive pressure or stress different from zero is sufficient for a glass to flow at any temperature,” he said. “The time it takes to deform depends mainly on temperature and chemical composition. If the temperature to which glass is submitted is close to zero Kelvin [absolute zero], it will take an infinitely long time to deform, but if it is heated, it will at once begin to flow.”

        • Calavera@lemm.ee
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          9 months ago

          You are telling me that if we heat glass it would deform? Who would have thought about that right

          • Muehe@lemmy.ml
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            9 months ago

            Heat in this context means any temperature above -273.15°C. Steel doesn’t display liquid properties at “room temperature”, glass does.

        • botengang@feddit.de
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          9 months ago

          Their ultimate fate, in the limit of infinite time, is to crystallize.

          Alright, but the article is talking about long to infinite timescales. The discussion above was about church windows and that is not caused by glass flowing.