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Is Glass Solid?        

glass exterior of skyscraper

Flow State

Glass looks and feels solid, but it isn't entirely so.

Glass begins as a molten liquid substance that gets spun and blown into various shapes, and continues to flow long after it cools.

If you look at glass under a microscope, it appears as though glass never really stops flowing to settle into a truly solid crystalline structure. The molecules in glass flow very, very slowly--so slowly that it would take millions of years for a pane of glass to flow in any perceptible way.

Pane-stakingly Slow

But does glass eventually stop flowing, even if it may take millions of years? That's a surprisingly tricky question that's baffled scientists for years.

A team of researchers from England and Japan may have found an answer: Looking at glass molecules under very low temperatures, they found that the molecules do appear to eventually form into solid geometrical shapes. Glass becomes solid eventually--but at a pane-stakingly slow pace!

Read More:

"Is Glass a True Solid?" (


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