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Unexpected Solidlike Fracture in Simple Liquids

quantamagazine.org

21–30 of 68 posts

Re: Unexpected Solidlike Fracture in Simple Liquids

#21

Earlier quoted context omitted.

I thought glass was a solid?

Nope, lots of fluids that just flow over such a long period they appear solid.

Not sure why klustregrif got flagged - the answer was informative and correct.

What I said is true but not for glass. Pitch is a liquid even though it feels like a solid and shatters when smashed.

Re: Unexpected Solidlike Fracture in Simple Liquids

#22
post #7

This looks like silly putty behavior.

Oobleck (corn starch and water) will do this too. But presumably they already knew that. The article describes it as being known to happen in “complex fluids,” but that it was news that it happens in “simple fluids.” Presumably silly putty and oobleck are “complex fluids?”

Specifically they're the subtype of non-Newtonian fluids, and it's also a colloid, and certainly is very elastic.

Re: Unexpected Solidlike Fracture in Simple Liquids

#23
> a project in collaboration with the oil and gas company Exxon Mobil

I find it a bit dark that, at a time people, crops, forests and biomes are dying due to extreme heat caused by the fossil fuel industry’s reckless behaviour the last 50 years, the said fossil fuel industry funds research on exotic rheology.

Re: Unexpected Solidlike Fracture in Simple Liquids

#25
I must be missing something.

If something is a fluid... or at least a liquid... that means it... flows, right?

Flow speed isn't infinite, so whenever you pull apart a liquid, you'll see some remnant of the pre-flow state. The thicker the liquid, the slower you need to pull it apart to see that.

Is this surprising? Why wouldn't every liquid do this? In what way is this somehow special to some liquids and not others?

Re: Unexpected Solidlike Fracture in Simple Liquids

#26
post #23

> a project in collaboration with the oil and gas company Exxon Mobil I find it a bit dark that, at a time people, crops, forests and biomes are dying due to extreme heat caused by the fossil fuel industry’s reckless behaviour the last 50 years, the said fossil fuel industry funds research on exotic rheology.

well unless you figure out how to replace plastic..

Re: Unexpected Solidlike Fracture in Simple Liquids

#27
post #23

> a project in collaboration with the oil and gas company Exxon Mobil I find it a bit dark that, at a time people, crops, forests and biomes are dying due to extreme heat caused by the fossil fuel industry’s reckless behaviour the last 50 years, the said fossil fuel industry funds research on exotic rheology.

They care about rheology because that expertise enables fracking, and they're smart enough to understand that you have to fund basic science to get (valuable) applied science.

Re: Unexpected Solidlike Fracture in Simple Liquids

#28

Someone tell me the industries that are going to benefit the most from this in the short and long term and what I can expect to see in the next 30 years as a result of this discovery.

Maybe I'm wrong or too naive... but isn't it related to "cavitation"?

Re: Unexpected Solidlike Fracture in Simple Liquids

#29
Second comment for a semi-off-topic question: does the state of matter depend on the gravity?

Thought-experiment: take any solid, put it in an infinitely strong cup, and crank up gravity. At some point gravity overwhelms the forces holding the substance together and thus the substance ends up breaking apart and.. filling the cup just like a liquid, no?

Does everything become liquid-like at sufficiently high gravity? How does one distinguish what's a solid or a liquid when gravity seems to make them behave similarly?

Re: Unexpected Solidlike Fracture in Simple Liquids

#30
post #23

> a project in collaboration with the oil and gas company Exxon Mobil I find it a bit dark that, at a time people, crops, forests and biomes are dying due to extreme heat caused by the fossil fuel industry’s reckless behaviour the last 50 years, the said fossil fuel industry funds research on exotic rheology.

This is the same company whose research funding was among the first to produce forecasts of these affects. Yet that didn't stop them.

Can't get more "dark" than that.

https://en.wikipedia.org/wiki/ExxonMobil_climate_change_deni...

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