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Unexpected Solidlike Fracture in Simple Liquids

quantamagazine.org

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Re: Unexpected Solidlike Fracture in Simple Liquids

#51

Post by ozlikethewizard »

computomatic wrote: post #36
autoexec wrote: post #32

Earlier quoted context omitted.

We could replace a large number of plastics right now and be just fine. Society flourished and thrived before we used plastic for everything in our lives. Some people would make less profit though, so of course it's impossible to make those kinds of changes, but we could.

Well, the mainstream adoption of plastics following World War II happens to coincide with an unprecedented period of relative global stability known as the “Long Peace.” So there’s at least some version of “thriving” that was, in fact, not previously achieved. Correlation does not imply causation but in this case it’s difficult to disentangle which innovations have lead to the relative global prosperity that has enab…

The classic US take on global peace, ask the Koreans, Vietnamese, Iraqis, Afghans, etc, how they feel about the long peace?

Moreover, pretty sure it was nuclear weapons, not plastic, that stopped the imperial powers from directly attacking one another.

Re: Unexpected Solidlike Fracture in Simple Liquids

#52

Post by HPsquared »

immmmmm wrote: post #44
MengerSponge wrote: post #27

Earlier quoted context omitted.

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.

I have worked half of my life in both fundamental and applied science, I know how this work. In particular you can refuse jobs you deem unethical. Why not funding energy transition research for instance. It’s know to science for half a century we’ll cook to death if we don’t phase out fossil fuel energy. And by know, I mean there’s literally millions of papers on the topic.

For my own small country, I'd rather we worked on how to adapt ourselves to the inevitable climate change that is coming, which we can't stop.

Re: Unexpected Solidlike Fracture in Simple Liquids

#53

Post by nervousvarun »

Asmod4n wrote: post #46
kulahan wrote: post #39

Earlier quoted context omitted.

Society flourished without lots of stuff we have today. It just flourished less. And people aren’t failing to migrate away from plastic because “somebody would make less money”, they’re using plastic because everything else basically sucks in comparison. It’s tough, cheap, light, stable, easy to shape, doesn’t often break dangerously, can have all of its basic properties modified, and more. Nothing else is THAT good.…

All we need to do is to replace all plastics with bio degradable ones. But I guess that will take some time since we don’t have replacements for all petroleum based plastics yet. Hopefully this will get us recycling friendly plastics for foods in the long run since those just get burned nowadays cause you can’t recycle those we have today for that job.

Agreed but for it to happen implies altruistic, non-profit based corporate decision making R&D & subsequent manufacturing etc.

No doubt the innumerable shareholder overlords out there who place the basic good of humanity over profit are pushing for it as we speak!

Re: Unexpected Solidlike Fracture in Simple Liquids

#54

Post by rsfern »

autoexec wrote: post #33
klustregrif wrote: post #18

Earlier quoted context omitted.

That’s a misconception. Glass does not flow over time; it is a rigid, amorphous solid. The uneven thickness seen in old cathedral windows is a result of historical manufacturing. Glass was spun into discs that naturally became thicker at the edges, and builders installed the heavier side at the bottom for stability. Physicists calculate that it would take longer than the age of the universe for room-temperature windo…

> That’s a misconception. Glass does not flow over time;...Physicists calculate that it would take longer than the age of the universe for room-temperature window glass to visibly deform under gravity. so then it does flow over time, just not on a scale where it matters to us.

But this is true for lots of solids, not just glass. Consider creep deformation [0] which is deformation mediated by diffusion of defects in solid materials. It’s a big problem in metal turbine blades, it limits the maximum usable temperature to well below the melting point.

The physical mechanism would be similar in glass flowing in this way, so I don’t think evidence of glass flowing like this should make us think of it as a liquid instead of an amorphous solid

0: https://en.wikipedia.org/wiki/Creep_(deformation)

Re: Unexpected Solidlike Fracture in Simple Liquids

#55

Post by immmmmm »

HPsquared wrote: post #52
immmmmm wrote: post #44

Earlier quoted context omitted.

I have worked half of my life in both fundamental and applied science, I know how this work. In particular you can refuse jobs you deem unethical. Why not funding energy transition research for instance. It’s know to science for half a century we’ll cook to death if we don’t phase out fossil fuel energy. And by know, I mean there’s literally millions of papers on the topic.

For my own small country, I'd rather we worked on how to adapt ourselves to the inevitable climate change that is coming, which we can't stop.

Adaptation is not an alternative for mitigation. We have to do adaptation AND mitigation (drastic reduction of emissions).

We can stop CC, science is very clear on this.

Re: Unexpected Solidlike Fracture in Simple Liquids

#56

Post by [deleted] »

dataflow wrote: post #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?…

[deleted]

Re: Unexpected Solidlike Fracture in Simple Liquids

#57

Post by dzhiurgis »

immmmmm wrote: 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.

The disease is consumerism, not industry. As long as there is demand - there will be supply. AFAIK no people weaned themselves off fossil fuels yet. Even basics haven’t been solved yet in most parts.

Re: Unexpected Solidlike Fracture in Simple Liquids

#58

Post by mjevans »

dzhiurgis wrote: post #57
immmmmm wrote: 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.

The disease is consumerism, not industry. As long as there is demand - there will be supply. AFAIK no people weaned themselves off fossil fuels yet. Even basics haven’t been solved yet in most parts.

At scale that is never going to happen.

Stop even thinking of conservation, start thinking of how to produce the desired effects using alternate sources and then apply regulation to move to those sources.

Solar, wind, tidal, geothermal, nuclear of any sort that's safer than coal or oil? Build it ALL.

Inexpensive energy is the cornerstone of advancing quality of life.

Re: Unexpected Solidlike Fracture in Simple Liquids

#59

Post by dataflow »

Mielin wrote: post #47
dataflow wrote: post #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?…

https://i.pinimg.com/originals/a1/fb/66/a1fb663d7d2942c1988d... If you put a cup of water in a strong enough gravity, lower part of the cup will have higher pressure, and that part will turn to unusual ice types. While top of the cup will remain liquid. Cranking up a gravity will only change the ratio. This is why people use pressure instead of gravity, pressure is what defines the state. Your main point is something…

Interesting, thanks!

Re: Unexpected Solidlike Fracture in Simple Liquids

#60

Post by mjevans »

scheme271 wrote: post #45
evaneykelen wrote: post #43

Earlier quoted context omitted.

I lived in a house built around 1605 in the Netherlands, with some of the windows being hundreds of years old, based on expert opinion. The glass had started to droop downward in certain places, almost like the resin you see in trees. It made me realize that glass is not as rigid as I thought.

I think that glass flowing thing is a myth. The manufacturing method back then resulted in uneven panes and they were installed with the thicker side at the bottom.

I'm not entirely convinced it is a myth, but the practical effect surely is.

I do suspect that over insanely long periods an otherwise undisturbed physical object would flow-sag at some rate under the influence of a constant force in a given direction.

No idea how long that would take, but erosion and other destructive forces appear to dominate so for practical measures any such effect is likely against the noise floor.

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