▲ 110 points
back
93 comments
Somewhat related is the hydration shell around molecules especially proteins. It’s been shown that semi structured water around proteins help guide molecules to reaction sites. Water is an amazing thing!
This is a molecular dynamics (with a specific TIP4 water model) and AI. I would characterize this paper (and basically most MD/AI simulation) as "guided hypothesis generation". I am skeptical that this result will hold up to experimental validation. It is incredibly easy to generate molecular dynamics results that look perfectly reasonable but have nothing to do with "reality" (i.e., how a lab experiment with the same system would turn out.)
One of the biggest challenges with water is modeling proton transport (i.e. pH, as water is a weird self-ionizing material.) Protons move too fast for MD steps to be stable, so they have to be approximated in some way. That is one reason why there are so many water models to choose from. Each model has a trade-off that is fine in some contexts, disastrous in others.
My money is on a TIP4 artifact.
There's plenty of experimental evidence for similar things. That's why I made a comment on this earlier about how it relates to it. Check my comment or https://www.science.org/doi/10.1126/science.aec0018 or https://www.nature.com/articles/ncomms3401
Study published in Nature Physics: https://www.nature.com/articles/s41567-026-03301-8
>The boundary between them is thought to terminate at a "second critical point." This deeply supercooled region is so hard to study experimentally because water crystallizes rapidly
This sounds like the type of thing that could be used for some future technology that doesn’t exist yet and I can’t comprehend. Some sort of process that takes advantage of being in this second critical state.
> some future technology that doesn’t exist yet
This is not usually how technology progression works when you see it play out.
More likely, it would be something like a 2% more efficient refrigerator. These advances stack up for a hundred years and build into something that looks like magical future technology.
There were very very few exceptions to this in history.
Could someone explain why raising standing water temperature to boiling, I see a constant stream of bubbles forming at the bottom of pan and floating up? Was there air between the water molecules to begin with? Any articles to help explain? I understand the obvious phase transition to gas which would escape at the top, but cannot quite grasp how we get the trapped air at the bottom.
Yes it's the dissolved gas in the water that comes out, see: http://scienceline.ucsb.edu/getkey.php?key=3197
So there is O2 dissolved in the water. Most of what I read explains we can boiling away O2 as seen forming on the side of the walls of a pot as temp rises. What's curious is why those bubbles seem endless if they have been expelled out, like some equilibrium of oxygen getting dissolved again back into the water.
Disclaimer: I am not a physicist and this is merely semi-informed speculation by an amateur enthusiast of understanding physical phenomena.
I had assumed that those were steam bubbles, not air bubbles. At high enough temperatures water becomes a gas. In a boiling pot, the highest temperatures are at the bottom. Temperature fluctuations on the bottom would lead to more steam production in some areas than others.
Any point at the bottom of the pot that did form a steam bubble would immediately lose energy to the steam and cool down. Now we likely are thinking of metal pots in this exercise, and metal conducts heat very well, so that cooled down point in the metal would draw nearby heat from the pan towards it, decreasing the chances of bubbles nearby. This would presumably lead to bubbles forming at some reasonable distance from each other, as any bubble formation causes the nearby pot metal to cool down.
Once in steam form, the steam bubble has a harder time losing energy. The energy was gained through direct contact of water with metal, but steam is much less dense, and it seems like the high-density shell of water around the steam bubble would act more like a mirror - reflecting the kinetic energy back into the bubble. This would keep the bubble stable as it travels up.
That's been my mental model of it for a while. It would be cool if someone who studied this stuff for real opined on it though.
a couple of breadcrumbs regarding the molecular organization of water.
Dissecting the hydrogen bond network of water: Charge transfer and nuclear quantum effects[2024]
https://www.science.org/doi/10.1126/science.ads4369
Resonance Character of Hydrogen-bonding Interactions in Water and Other H-bonded Species[2005]
> Much of the evidence for the LLPT has therefore come from computational studies.
So it's just a numerical simulation with some ML techniques?
"Density is greatest at 39F, not 32F"
But density at "greatest" would mean volume shrinking...right?
I don't understand the article's logic.
Yes, exactly. Water occupies the least volume per unit mass (equally, per unit molecule) at 39F. As it cools further, it paradoxically begins expanding in volume (as the polar ends seeking out their opposites in other molecules introduce a loose order to the liquid randomness).
Then, suddenly, at 32F/0C, water's real miracle happens. All the loose molecules click into place with other molecules - well, nearly all, because ice cubes aren't monocrystalline, typically, but those spare unmatched ends of molecules at crystal interfaces are still trapped by their other ends, and any single molecule unable to "find" a match for either strongly attractive end will still be trapped as well into solid-matrix mechanics. At most, those solo unmatched molecules become slight diffaction points for phonons (sound-energy propagation), but they are in fact so rare and so slight that they are generally undetectable. (The crystal faces are made of millions of unmatched molecule ends, and have therefore much more effect.)
Other polar molecules can act similarly, but water is astoundingly smaller than most others - so its molecules "find" their matches more easily, as they don't need to "rotate" much mass to line up - and is much less flexible as a result (so the alignment on the two-molecule level forms a more rigid body than, say, a polar sugar, and the volumetric effect is more pronounced).
I wonder if we are finding structure here because we are looking for structure.
Similar how you can find human faces in random pixels or rocks.
Nah.
If I understand the article correctly, they found a phase transition reaction, a chemical reaction that occurs in liquid water below 0 C that splits the body of liquid water into one continuous region of high density and one of low, so its no longer a uniform liquid.
This would also release heat, like the freezing reaction (and unlike random rearrangements of molecules in the liquid).
Okay thats wrong they didnt find that. Looks like just did some ml and it suggested that such a reaction exists and what the two species are.
Also its unclear whether during the phase transition there really is two seperate macroscopic regions as opposed to a mixture (maybe like a suspension)
But what if we find the exact same face in different rocks or pixels? I also think the researchers were aware of this issue as the article mentions they were careful not bias their model.
Very interesting point though!
So the OTA firmware updates on my dehumidifier for when they discover a new kind of water will come in handy after all!
Dehumidifiers will end up being more efficient in one mode. When the manufacturer creates the new ones, a firmware update moves all legacy devices to the less efficient mode.
Nah, IFIFY: So the OTA firmware updates on my dehumidifier is for when they make a new kind of dehumidifier that they want me to buy!
Sadly paper is behind paywall. But I question the choosing of the water model to be a 4-site, and why that specific 4-site one (TIP4P) instead of others that have shown to be more accurate such as OPC. Also, there seem to be previous experimental work (https://arxiv.org/abs/1304.2877) showing some evidence that apparently is not even referenced in this new paper. I wonder how does that compare, if at all.
Your linked preprint has been also published in Nature Communications: https://www.nature.com/articles/ncomms3401
This neural network stuff does give me real divination vibes, not gonna lie.
"In a neural network." is the new "In mice."
Well put. That's exactly right. (And I don't even mind mouse studies!)
It would be hilarious if homeopathy turned out to be right!
(To be clear, I don't think that will actually happen, but it would be hilarious if it did!)
You can be sure they’ll start using this paper as “evidence” all the same.
Everyone does that. Not only "they"!
While on the topic of weird theories of water, there's always Polywater:
Your comment is in violation of the rule (applicable to comments):
> Eschew flamebait. Avoid generic tangents.
Avoid commenting with tangents that have nothing to do with the article. If you don't agree, the site moderator dang can explain to you with administrative action.
Homeopathic medicine is a discredited theoretical explanation for a phenomenon that empirical testing shows does not exist. For 'homeopathy' to be right, it would need the to become 'right' twice -
first: new data would need to begin existing, and then second: the homeopathic mechanisms would need to become the most plausible explanation for that data
>empirical testing shows does not exist..
But what are the incentives of those who did those tests? That should be said in the same breath as you say "empirical testing/evidence".
Don't know about right, but for a while it worked better than "regular" medicine. At least it wouldn't kill you, when the alternative was intensive bloodlettings and purgatives.
> for a while it worked better than "regular" medicine. At least it wouldn't kill you
Homeopathy was invented after the discovery of germ theory [1][2]. So not really. And homeopathy has always suffered from an adulteration problem.
As I recall homeopathy does pretty fine statistically compared to many treatments. Not because the water does anything, but because the provider has time, and talks to patients about their problems and life.
A lot of doctors are shoving people out the door based on their first thought inside a short appointment as they type up a prescription.
Homeopathy is ineffective kookery, but our medical system has some well known gaps.
Homeopathic medicine is already recommended by 1 out of 1000000000000000000 doctors.
Vaccines is homeopathy working, in a way :)
There is no basis to suggest that any product uses this property of water. As for homeopathy, it isn't one thing. The effects, if any, can vary greatly by the substance and the concentration. Some low-dilution products work and many high-dilution products don't. There is such a thing as excessive dilution. Anyone who is painting a simpler picture of it is almost certainly wrong.
"Water has memory, and whilst its memory of a long lost drop of onion juice seems infinite, it somehow forgets all the poo it's had in it."
- excerpt from Storm, by Nick Minchin
https://www.youtube.com/watch?v=HhGuXCuDb1U&t=353s
The entirety of this song is a listen worth your time. Doubly so if you've never heard of Nick Minchin before.
Wait, wouldn't it just be "Oh, science just made a mistake, and that is how it progresses"...
Despite the "consensus" thoroughly "debunking" it conclusively many times...
Also, if it ever happens, I think it would be during course of many decades that all the existing "scientists" can save their faces, and new generations won't care about "Science" being wrong once again, despite all the projections of "certainity" back then..
Great to see progress on ice-9 /s
"I have been a writer since 1949. I am self-taught. I have no theories about writing that might help others. When I write, I simply become what I seemingly must become. I am six feet two and weigh nearly two hundred pounds and am badly coordinated, except when I swim. All that borrowed meat does the writing.
In the water I am beautiful." ― Kurt Vonnegut, Welcome to the Monkey House
So if liquid water is really a mixture of water and water, is it safe to say that this paper establishes that water is wet?
Only if the molecules have a hydration shell
[flagged]
Eschew flamebait. Avoid generic tangents. Omit internet tropes.
Please don't use Hacker News for political or ideological battle. It tramples curiosity.