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Discussion (51 Comments)Read Original on HackerNews
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.
Can't get more "dark" than that.
https://en.wikipedia.org/wiki/ExxonMobil_climate_change_deni...
It’s somewhat a scale up of what the tobacco industry did, same strategies, etc
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.
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.
Edit: Not to mention, it’s not as simple as “don’t use plastic packaging anymore”. We pull oil into a machine and cook it off at various stages to produce various things. Turning cooking stage 8 of 12 into a worthless pile of garbage to be discarded doesn’t stop us from pulling in that oil for the other 11 uses.
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?
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 like "material becomes weak compared to gravity, conforms to the cup, as if liquid", or "cant have long range structure". But we already have solids that are like that - sand. Sand doesnt resist change to its shape, it just slides in a new position. And yet we still consider sand to be solid. Angle of a pile in particular.
Even a neutron star likely has surface level irregularities on a scale of centimiters. While a liquid can flow to submicron level smoothness even in a diy experiment.
Material gets stronger as pressure is increased. Unusual crystal structure becomes available. Superconductors and some other weird properties can exist only when crystal structure is compressed. And this tendency continues all the way to degenerate matter, as in neutron stars. Material from inside of a neutron star is likely the strongest a material can be in this universe.
So in the end, "solidness" continues to fight back, presenting enough properties to differentiate it from a true liquid, even if it could look somewhat similar, "shallow pile of material", all the way to degenerate matter of neutron stars.
[edit: but glass is not a simple fluid.]
The "well it's technically a liquid!" because it "flows" is really not telling the whole story. Like most science, it's just more complex than can be quickly summarized with one sentence, and doesn't quite map to just high school simplifications.
What I said is true but not for glass. Pitch is a liquid even though it feels like a solid and shatters when smashed.
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?
But then again I suppose if you lead a cosseted life, never played with the contents of a shed, and had your first practical experience of actual hands on behaviour of viscous liquids in a lab… you might shout “Eureka”.
(Off the top of my head, a material that dissipates tension below a certain rate but fails when it is applied faster than that rate seems to resemble a mechanical breaker. As in not an electrical breaker that works mechanically. But one that decouples when you pull on it super hard. Being able to do that in fluids means one can potentially do that at very tiny scales.
More broadly, if simple fluids have a quasi-elastic mode, that has fundamental implications for hydrodynamics. I'd be super curious to know, for example, if anything similar to this occurs in air or water.)
Oh, btw: electricity was a novelty toy for several long decades with no major practical applications. But that eventually changed because people kept researching it. And it changed the world.