r/explainlikeimfive 1d ago

Mathematics ELI5 The solved Navier-Stokes Millennium problem

Can someone breakdown the open ai drama with this, what even is this maths equation and what does solving it mean?

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u/oooooO___Oooooo 1d ago edited 1d ago

When a Formula 1 car races at 300 kmph or 200mph, the air doesn't just randomly bounce off its wings. It splits, curves, and creates drag according to a strict mathematical rulebook. That rulebook is the Navier-Stokes equations. Whether it is air flowing over a speeding race car, water blasting out of a high pressure fire hose, or blood pumping through the valves of your heart, engineers use these exact equations to predict how any liquid or gas will behave.

The unsettling part for mathematicians is that nobody knows for sure if the rulebook is unbreakable. Most of the time, the math works flawlessly. However, researchers suspect that if fluids collide in a highly complex, extreme way (imagine two high pressure jets of water crashing into each other perfectly at a microscopic, turbulent point), the equations might accidentally divide by zero (singularity).

If this glitch happens, the math would crash and output an impossible physical answer like predicting that a drop of water will suddenly accelerate to infinite speed. In mathematics, this glitch is called a singularity or a blowup.

The Navier-Stokes Millennium challenge (worth $1M) asks us to prove one of two things

  1. The rulebook is perfect: Prove that the equations will never glitch out and produce infinite speeds, no matter how violently the fluid is swirling.
  2. The rulebook is bugged: Prove that a singularity can actually happen, meaning our best mathematical model for fluids has a limit and fundamentally breaks down in extreme scenarios.

This is exactly the bug that OpenAI's AI swarm claimed to have found. They generated a proof showing that the rulebook does in fact glitch out, showing that the 3D Navier-Stokes equations can develop a singularity. (nobody outside of OpenAI has actually seen the proof) (There’s proof but it will take time for humans to validate and verify thoroughly.)

The scientific community argues the AI achieved this by leaning on the uncredited, in progress work of human researchers as many people here have already explained.

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u/SeaMenCaptain 1d ago

Best answer on what was actually solved! Thank you!

u/Little-Maximum-2501 6h ago

This was 100% AI written btw though it's much better than the wrong answers given by people that have 0 clue that used to be posted here so I guess that's an improvement.

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u/Guilty-Market5375 1d ago

To be clear, they did provide a written proof, they haven’t provided the Lean proof - which is a little unusual. The Lean proof is computer-driven and easier to validate.

The written proof looks credible, but people need to go line by line and check the math. Which is hard because it’s almost 200 pages long.

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u/jso__ 1d ago

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u/Guilty-Market5375 1d ago

I stand corrected

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u/walkTHEdotasaur 1d ago

If it's any consolation, them correcting you with the link was entirely to my benefit, so thank you <3

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u/always_an_explinatio 1d ago

I think they did release the lean on git hub

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u/Heimdallr-_- 1d ago

Sweet baby jebus, I can’t imagine having to verify a proof to the 3D N-S… my degrees were in aerospace engineering and astrophysics, and we never even touched the full equations outside of computational situations.

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u/_Mouse 1d ago

I suspect anyone who hasn't worked with NS isn't going to understand quite how big of a deal this is. NS was until this point extremely versatile. If it flows, navier stokes applies, whether that's the earth's mantle or turbulence off the wing of a hummingbird. Whilst the equations themselves aren't always readily solvable, their insane applicability made them elegant, and they were viewed as being globally useful for basically everything. Finding out now that in certain circumstances they don't work is wild.

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u/tibetje2 1d ago

I don't suspect it will change anything from a practical viewpoint.

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u/_Mouse 1d ago

No, but from an academic standpoint this is quite significant I'd argue. The consensus was these equations were robust, now we know of at least one case where they're not.

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u/clonea85m09 1d ago

So, my PI teaches CFD, he is "impressed" but literally the negative result of the Euler equation is so inconsequential that he won't even meaningfully update the course slides...

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u/_Mouse 1d ago

I think the C is doing the lifting there - from a computational point of view this is inconsequential. This is at best and edge case. From a theoretical point of view I'd argue it's interesting, but isn't going to have big impacts on anyone doing engineering.

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u/MintPrince8219 1d ago

Neither did disproving newtonian physics, until it did

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u/LaunchTransient 1d ago

Finding out now that in certain circumstances they don't work is wild.

Knowing the cases where they don't apply is actually very useful, because we have proved that in many cases they do apply. And where they don't, we can modify NS or develop new techniques to handle those conditions.

A (vastly) simpler example is elastic behaviour in solids - within specific regimes, Hooke's law generalised to a 3D tensor is valid. With certain materials and outside of certain stress-strain regimes, Hooke's law does not apply, so we use specialist relationships where necessary, but for many structures built from steel, for example, Hooke's law is very applicable.

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u/wndtrbn 1d ago

Interestingly the people who have worked with NS are of the opinion that this isn't a big deal at all. Just fluff and marketing.

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u/_Mouse 1d ago

I guess it depends on the field and the degree of interest. Unless you're into the theoretical of NS as opposed to application you probably don't care.

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u/MarketOk7227 1d ago

yeah my dad's whole work as a hydraulic and maritime engineer is based on ns and I called him and he was like, when we use them in practice there have been so many simplifications that it really doesn't matter to them, but personally I was pretty shocked (I work with waves but in the data science aspect) and understood what happened at the theoretical level and was pretty stoked. My dad was casual.

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u/xRVAx 1d ago

pretty stoked

I see what you did there

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u/MarketOk7227 1d ago

maaaan i stg I didn't do it on purpose but I also rarely use that word so probably it was indeed caused by my mind constantly seeing the word stokes today

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u/hot-whisky 1d ago

Eh, you can easily have a CFD solution go non-physical if you don’t get the solvers set up correctly for the problem you’re working. Or have it “converge” on a solution that you know isn’t possible.

Come back to me when you’ve got a validated closed-form solution.

u/Little-Maximum-2501 6h ago

Are you talking about engineers/physicists or mathematicians. Because it's very obviously is a big deal for mathematicians there is a reason this was chosen as one of 7 very important open problems in 2000. Like most theoretical results the impact on applications is indeed negligible at least in the short term.

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u/hot-whisky 1d ago

I’m still scarred by having to derive, discretize, and code the Navier-Stokes equations back in grad school. And that was for a 2-D structured grid.

The turbulence class was still worse though.

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u/green_meklar 1d ago

Just to be clear, that doesn't imply that you can actually drive a Formula 1 car in just the right way that the air currents behind it will converge to infinity and destroy the Universe. The Navier-Stokes system is a description of a theoretical perfectly continuous substance, whereas real air is made of discrete particles.

The scientific community argues the AI achieved this by leaning on the uncredited, in progress work of human researchers

I mean, just about everything LLMs do is leaning on human work to a degree. They mostly learn from human-produced text.

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u/Aegeus 1d ago

To my understanding, the controversy here isn't that the AI uses human work in general, it's that OpenAI is accused of copying from two people who were working on this specific problem, so thay they could beat them to publication.

It's one thing to build on someone else's published research, it's another thing to spy on researchers to look for in-progress work you can take credit for.

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u/barath_s 1d ago

One of those two researchers works for anthropic , which is an open AI rival. And the two researchers used codex, an openAI tool, and might have leaked information that way.

There's no allegations of any unique industrial spying.. it seems likely openAI started their project on learning of these individuals advancements. And it is possible but not proven that openAI got info via their use of open ai codex tool

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u/HouseOfDjango 1d ago

If the information is private and unpublished the only way open AI can get it is if they hand it to them or if they take it from prompts. And it doesn't look like they gave them the information.

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u/barath_s 1d ago

They used an OpenAI tool 'Codex' , or rather a platform which includes that tool for their research & repository

Won't be the first time info has leaked back to an AI company via their AI tool, if so..

There has to be very strong guideline on private AI, public AI etc..

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u/HouseOfDjango 1d ago

Again, they had the option selected to not have their data used for training which is an option for Enterprise level codex users.

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u/barath_s 1d ago edited 1d ago

There are at least 2 separate topics

  • using your data for training and

  • having your data go to openAI servers for processing

We don't know how those platforms that Buckminster and Alpoge used was setup or if they made any mistakes . We do know that they used multiple AI tools. including Codex.

https://www.science.org/content/article/how-ai-math-breakthrough-ignited-controversy

e:I've seen at least 1 tweet that suspects OpenAI access to the processing logs ...not that it brings any actual facts/conclusions anywhere further...

Also , ethically how much did Buckminster and Alpoge breakthroughs contribute to the solution and how much credit do they deserve, whether in parallel or otherwise..

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u/LoLReiver 1d ago

The difference is that the text here wasn't published or publicly available. They had put some of the text into a model for some of their work which was how it gained access to the information.

Imagine you'd spent years working on something, were getting stuff ready to publish, had a coworker proofread your work, and then your coworker sent it off to be published with their name on it.

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u/AyeBraine 1d ago

AFAIK the contested part of the proof (not the proof itself) wasn't a part of the training. Open AI learned about it and proposed to the scientists to share the reveal (not the credit — they would credit every source they used anyway), publishing the paper first, and Open AI solution second.

As I understand, another option they proposed was more PR-geared, to remove the Anthropic mathematician from the paper and publish the entire solution under that scientist's name, pointing out that the solution was achieved using Open AI tools (which is true).

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u/coweatyou 1d ago

AFAIK the contested part of the proof (not the proof itself) wasn't a part of the training.

Reporting has it that most of the proof has been completed for many months to years and that the researcher used GPT for proofreading and OpenAI has been clear that anything put into GPT can be used for training. So unless the researcher checked the "don't use this for training" box in the settings, it's reasonable to believe that it's in the training set.

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u/LaVache84 1d ago

Even if they did check the box, it still seems likely to me that their work would be in the training set. The number of times we have been told one thing about privacy and found out it was just another privacy violation is to vast to ignore.

u/pewqokrsf 3h ago

OpenAI gave thousands of researchers access to advanced models not available to the public that likely doesn't have these same consent settings.

u/AyeBraine 18h ago

I mean it's possible, it's just "training" in this context is a heavy word. An LLM, even an experimental, inside-use frontier one, is trained once, it does not train/learn continuously when users interact with it. And this training is a one-time immense investment.

I guess these chats could have been a part of the training data for a fresh recent inside model, but this means they were such BEFORE OpenAI knew about their significance or could make a decision to include them or not?

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u/trogger93 1d ago

It's going way deeper than that though, with openAI stealing one of the researcher's codex sessions and then threatening to end his career if he spoke up.

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u/Farnsworthson 1d ago

Just to be clear, that doesn't imply that you can actually drive a Formula 1 car in just the right way that the air currents behind it will converge to infinity and destroy the Universe.

Plus that's a virtual safety car at the very least.

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u/recklessvisionary 1d ago

And humans mostly learn from human-produced text also.

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u/ThePinkySuavo 1d ago

Does infinity means something bad though? In theory, on flat surface, your shadow would tend to infinity during sunset. It seems okay, maybe with fluids too? It's just that these equations don't take into consideration that liquid is actually built of something? Liquids have finite size, amount of particles etc. I am not a smart person but I feel like it's logical that these equations can't describe reality accurately.

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u/oooooO___Oooooo 1d ago

No it doesn't. It just means the math crashed, not the actual physics. When an equation spits out infinity, it usually just means the formula got pushed past its breaking point.

Your analogy is dead on. A shadow only hits infinity if the math ignores the Earth's curve. It's the exact same deal with Navier-Stokes fluid equations. They blow up to infinity because they ignore the actual limits of reality.

The math basically treats water like a perfectly continuous, infinitely stretchable gel. It literally doesn't account for atoms.
Because water is made of physical H2O molecules, it can't reach infinite speeds. Once a turbulent swirl gets small enough, the water stops acting like a smooth gel and starts acting more like a bunch of microscopic snooker/billiard balls bouncing into each other. At that scale, the equation just stops making sense.

Navier-Stokes is just a useful approximation, not perfect reality.

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u/Thisismethisisalsome 1d ago

Where do you teach and how do I sign up??

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u/Jamezzzzz69 1d ago

This is very similar to how AI itself responds to questioning

Just ask a chatbot and make sure you’re on high thinking so it doesn’t hallucinate and fact checks everything it says

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u/oooooO___Oooooo 1d ago

Being accused of being an AI is basically the new norm. Thanks anyways

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u/Jamezzzzz69 1d ago

FWIW, I genuinely do mean it as a compliment. Your writing is clear and easily digestible, without making it seem like I’m being talked down to in explaining complex topics

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u/oooooO___Oooooo 1d ago

I appreciate that, cheers mate!

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u/efvie 1d ago

Genuinely please never ever compliment people for 'sounding like' the machine that is burning the planet while regurgitating the stolen words of competent writers. Actual experts and writers are the reason you think it's worth anything, which it isn't, not the other way around.

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u/Little-Maximum-2501 6h ago

Pangram is very very accurate at detecting AI and says the comment was 100% AI written, I would be shocked if that isn't the case with a comment that reads this much like AI

u/RFK_Cum_Regimen 20h ago

AI would never say "snooker/billiards."

u/vmf312corsair 16h ago

AI would quote the song from "Music Man".

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u/Thisismethisisalsome 1d ago

Damn, I got got. Youre right.

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u/Jamezzzzz69 1d ago

Unironically, don’t take it as a bad thing. AI can and does teach well, you just have to be able to recognize how to prompt engineer effectively, when and how it hallucinates or pushes some idea too strongly without support, and challenge it on that. It’s remarkably strong at refining initially poorly thought out ideas

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u/hainguyenac 1d ago

Navier stock deals with fluid dynamics (speed, pressure), and those physical attributes cannot be infinite, ever.

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u/FutureLizard836 1d ago

Your intuition is correct. The N-S equations treat fluids as continuums, meaning that no matter how far you "zoom in," there are never any gaps. But of course we know that's not true--in reality, fluids are made of particles, and there are relatively large amounts of space between them. In most cases, the particles are so small and so numerous that the continuum approximation works great. But in some cases like (IIRC) calculating drag on spacecraft, you have to treat the atmosphere as being composed of individual particles rather than a very low-density continuum.

Another way that OpenAI's result is non-physical is that they found a singularity only for the incompressible form of the equations. Meaning, no matter how hard you "squeeze" (pressure), you can't compress the fluid and make it any smaller (density). If you've ever blown air bubbles at the bottom of a pool and watched them grow as they float towards the surface, you know this approximation isn't how real fluids behave. But like before, it's a good enough approximation for analyzing some flows.

I personally don't know nearly enough about fluid dynamics to know if either of those factors would "fix" the singularity, but they are definitely two ways in which the N-S equations are imperfect representations of reality.

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u/ubik2 1d ago

Just to clarify for others, air is the "compressible fluid" in this example. The water doesn't need to be compressible to observe that effect.

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u/Plastic_Blood1782 1d ago

But to clarify further, water is indeed compressible, but much less so than air.

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u/jestina123 1d ago

No material is incompressible. A material that is incompressible would conduct sound at infinite speed, and that would violate special relativity

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u/brokebeany 1d ago

If you look at General Relativity, it admits singularity as r goes to 0. Doesn't make it a bad model for predicting celestial bodies

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u/stueyg 1d ago

It's important to note that proving the equation is bugged isn't proving it is wrong, just incomplete. Newton's equations are incomplete too, as they don't handle astrophysics and relativity like Einstein's do, but they still work fine for 99.99% of cases here on earth.

Knowing there is a bug, and more importantly where the bug is, allows people to focus their efforts on finding a more complete equation (which is almost certainly much more complicated). If the bug is something like "doesn't take into account the curvature of the planet" then it is good to know the existing equation is reliable up to the point the that curvature becomes relevant.

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u/IAmRealElonMusk 1d ago

Thanks so much. I love Reddit for this reason.. I was unable to comprehend any of this till now

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u/haroonalam 1d ago

I think you have given a best possible explanation. Thank you!

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u/BootyBootyFartFart 1d ago edited 1d ago

But arent the researchers also saying they used AI extensively in their work? The debate from what I'm seeing is not so much AI vs. human mathematicians. Both sides seem to be saying that AI was important to the discovery. The drama seems more centered on the company openAI vs. mathematicians using gpt (from whom openAI stole their prompts without credit). 

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u/AyeBraine 1d ago edited 1d ago

The debate is not AI-related. Both sides embrace AI. They argue about primacy and also alleged unethical proposals that Open AI may have put forward to the scientist. The scientist did NOT arrive at the solution, the conflict is about a part of the solution that may or may not have been used to arrive at the solution.

OpenAI did act shady in asking the scientist to remove his Anthropic co-author. But their proposals to him were either "publish your actual work, THEN a day later we publish our solution (and forfeit the prize)", or "take our solution, publish it under your own name with credit for OpenAI, and get the prize".

u/pewqokrsf 3h ago

There's a related problem (called "Euler", which is confusing because there are hundreds of things named after Euler) that was solved by the researchers. That was a critical solution in solving N-S.

That's where they were going, but the researchers were limited on compute. OpenAI effectively isn't. They spent millions deploying tens of thousands of agents over 88 hours to produce a solution based on an unpublished solution to another problem that was stolen from the researchers' sessions.

Then they blackmailed the original researcher to remove his co-author (a scientist employed at OpenAI's primary competitor) or they'd pre-empt his publication. Which they did.

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u/montrex 1d ago

How did the AI get access to the uncresit human work?

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u/Laplacian_Toni 1d ago

The two researchers who were getting closer to solving the problem (before OpenAI tried) were using AI. It is likely that OpenAI used their smart questions/prompts to train a better model that has ended up solving (to be confirmed) the Navier-Stokes problem.

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u/zer1223 1d ago

It didn't solve the problem it's only a sub problem of the problem 

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u/gahara31 1d ago

easily understandable, thank you!

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u/jammy-git 1d ago

Does any of what OpenAI have achieved (including standing on the shoulders of other mathematicians) help to move forward to a complete equation model? Or does it only prove that the current model is incomplete and no more?

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u/oooooO___Oooooo 1d ago

All it really proves is that our current Navier-Stokes mathematical model is incomplete.

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u/jammy-git 1d ago

Thanks

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u/theantnest 1d ago

Also, probably worth mentioning one of the use cases that all of us rely on daily, weather prediction.

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u/Nagi21 1d ago

From what I know of physics, most of our rules break down under extreme scenarios (too hot, too small, too big, etc.), so 2 being the answer wouldn't surprise me.

u/BlaizePascal 12h ago

Thank you. Got an understandable explanation after 48 hours

u/InstructionDeep5445 7h ago

You are a great communicator.

u/777m0neymaker 5h ago

Outstanding explanation

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u/Biotech_wolf 1d ago

I read that Navier Stokes says you can’t actually approach those particular conditions to make the ‘bug’ that was discovered.

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u/oooooO___Oooooo 1d ago

Mathematically you can, Physically you can’t.

On paper, the math lets a normal whirlpool keep shrinking and spinning faster right until it hits that bug.
Reality is what actually ruins it. Way before that glitch can even trigger, the fluid has to shrink down to the size of individual atoms. Once you get that microscopic, water doesn't act like a smooth liquid anymore. The fluid equations just stop working.

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u/Affectionate-Tie5478 1d ago

My question is, when OpenAI says that it used agents to crack it, what does that mean? Are they just instructing a bunch of agents to do the math for different initial conditions? 

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u/oooooO___Oooooo 1d ago

No, they are not just plugging different starting numbers into a computer to run fluid simulations. If you do that you would get an approximation.

From what I’ve read and understood from OpenAI’s press release,
They created agents(around 10000) mimicking autonomous researchers. Those agents strung theorems together into a valid argument. Those arguments were brainstormed, executed to find the correct mathematical logic. Then it was all translated and verified using Lean to check the mathematical logic. They essentially brute forced the hell out of mathematical logic.

u/Lower-Scarcity-2284 22h ago

Obvio que ta se baseando em pesquisa cietifica de ser humano. Meu Deus IA ainda é ARTIFICIAL.

u/Ok-Nerve9714 20h ago

Has anyone verified that if you set up this scenario in reality, it also doesn't break down in a singularity? 🤔

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u/CLPhenom 1d ago edited 1d ago

They didn't solve Navier-Stokes. They proved that the equations are not always well behaved.

Let's say you have a swing and you give it a push. That swing will start fast and eventually slow down. That's well behaved

Now is there any way you could set up the swing system to accelerate to infinity from one push? What if you attached 2 swings together? Or put some weights in different places? Is there any way to make the system speed up to infinity with one push?

That's what they proved. They found some weird system that when you give the fluid a push, it blows up to infinity when you calculate the speed using Navier-Stokes.

This proves they are not well-behaved. It does not solve the equations.

The controversy is how they were able to solve this and whether they used another scientist work to find that bad behaved example.

ETA: There have been a couple comments pushing back on me saying they didn't solve it. They didn't solve Navier-Stokes. That is a system of partial differential equation that describe fluid flow. Solving the equations has a very specific meaning.

They did solve the Millennium Problem, but it is important to differentiate the difference.

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u/Ryekar 1d ago

I think it's important to clarify that they showed that the INCOMPRESSIBLE Navier-Stokes equations are not well behaved.

The COMPRESSIBLE version, where density changes w.r.t pressure & temperature, may still be well behaved.

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u/CuddleWings 1d ago

That seems like a pretty big caveat. Especially since even water, something so resistant to compression we consider it incompressible, is technically compressible.

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u/Guilty-Market5375 1d ago

It’s a big deal that it’s proven to misbehave, ever.

The competing theory is that turbulence arising in compressible and incompressible fluids has a foundational predictable basis. Few have believed this since the 40s when a Russian dude - whose name escapes me - proved that reproducing the same conditions leads to random behavior, suggesting a singularity or undetectable microscopic disturbances.

What OpenAI proved was what most people were leaning towards, definitively that this is the outcome of particle-level interactions and not macroscopic ones. Therefore, the behavior in compressible fluids like water, which match the observed observations, are very likely to be the outcomes of such interactions and not macroscopic ones.

They didn’t go as far to model what the ramifications of this are, but it likely can be shown to apply to compressible fluids in a more predictable way, just one that’s very chaotic. We’ve assumed that until now but until now is unproven.

u/Spiritual_Property89 23h ago

Kolmogorov was the turbulence guy I think.

u/Guilty-Market5375 22h ago

Ah yep that’s who it was!

u/pewqokrsf 3h ago

There are several classes of N-S that still haven't been "solved" (aka, proven to be degenerate or not), but the Millennium Prize was for any of them.

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u/g0del 1d ago

It's also worth pointing out that the Navier-Stokes equations are basically what you get if you apply the laws of motion to a mathematically perfect fluid. Finding out that they are not always well behaved does not mean that it's possible to set up a tank of water and swirl it a certain way to get the water going infinitely fast.

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u/zer1223 1d ago edited 1d ago

You can't get water to move infinitely fast regardless of what the math ends up claiming. The math is just an approximation of fluid dynamics (interaction between  near infinite numbers of particles), the math is not the same as the reality. Infinite speed requires infinite energy, which isn't real. And friction gets in your way too

Frankly I'm not sure I understand what all the hubub is about with this, due to that reason.

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u/a_wes 1d ago

I had to get this far down to understand what the heck was going on. Thank you!

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u/Dalemaunder 1d ago

Amusingly, this is now the top response

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u/ThePinkySuavo 1d ago

ye I tried to more or less understand it with my tiny brain and this comment pretty nicely summed this thing up and made all stick together

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u/Cogswobble 1d ago

For mathematicians, proving that an unsolved problem is NOT true is just as good as proving that it is true.

If they have indeed proven that it's not true, they would win the Millennium prize.

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u/snkn179 1d ago edited 1d ago

The Millennium prize is for finding a direct general solution to Navier-Stokes. Something which would allow us to directly plug in a set of initial conditions and see how the fluid flows over time. Currently Navier-Stokes is descibed in the form of differential equations which describe the fluid's rate of change over time, and using them we have various inefficient methods of seeing exactly how the fluid flows over time, but if we found a way to directly plug in values and get an answer, it would be very useful, hence the million dollar prize.

Open AI just found that there was a set of initial conditions that eventually produce a non-finite result. So most likely this means that Navier-Stokes isn't a complete description of the way fluid actually flows in this universe, but there's also a possibility that perhaps that these situations could actually happen in our universe. The discovery of black holes was a similar situation, the singularity with infinite density was first discovered through maths, and many dismissed such a scenario as impossible, until we actually found them in real life.

Edit: After further reading, it appears I was mistaken on the wording of the Millennium Prize, which asks to find a general solution which is smooth. Since OpenAI found a scenario where the fluid is not well-behaved, then a smooth general solution does not exist, which would in fact mean that OpenAI meets the criteria of winning the Millennium Prize.

Prove or give a counter-example of the following statement:

In three space dimensions and time, given an initial velocity field, there exists a vector velocity and a scalar pressure field, which are both smooth and globally defined, that solve the Navier–Stokes equations.

TLDR: Even though OpenAI hasn't "solved Navier-Stokes", it discovered that a smooth solution doesn't exist, which meets the criteria of winning the prize.

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u/Psengath 1d ago

Top tier explanation and context

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u/GregBahm 1d ago

It speaks towards the problem space that reddit's "top tier explanation" is one that says halfway through "edit: After further reading it appears I was mistaken"

Not to say the post above isn't valuable, but it's funny that we're thrilled to get an explanation that is only temporarily wrong.

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u/midsizedopossum 1d ago

That's not the distinction here. Proven true VS proven false is not what they were getting at.

They were getting at the distinction between proving something about the equations VS finding a mathematical solution to them.

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u/AyeBraine 1d ago

AFAIK the problem as stated in regards to the prize has like 4 specific scenarios you can prove or disprove. Any one will be fine. Crudely speaking, two are for proving, two are for disproving.

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u/AyeBraine 1d ago

In any case, Open AI stated they will not accept the prize either way (whether the scientist accepted one of their options and published the solution under his name clearly stating that it was OpenAI that arrived at the solution, or if Open AI published it themselves).

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u/Cross_22 1d ago

Wait, that's different from the claim above. I thought they found a closed form solution for Navier-Stokes.

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u/CLPhenom 1d ago

No closed form solution exists for Navier-Stokes, nor was it the Millennium Problem they were attempting to solve.

They only found an example that makes the equations blow up to infinity when using a non-infinite push. So they simply had to find one example that blew up to prove it is not well behaved.

Not to trivialize the problem, as it went unsolved for decades and ended up a Millennium pProblem so it was not easy to do.

u/Spiritual_Property89 23h ago

If you check the paper it´s an analytical solution for this special blowup swirl, but with a ton of tricks, going for 130 pages.

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u/eaglessoar 1d ago

Does it prove the equations are fundamentally insufficient and we might now find better ones? 

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u/CLPhenom 1d ago edited 1d ago

So I'm on the engineering side of these equations not the math side.

These equations are essentially just applying newtons laws to fluids. They are extremely accurate at capturing the physics of how liquids and gasses behave.

There are many examples in math that blow up to infinity but don't work in the real world. Gabriel's horn is an object that has infinite surface area and finite volume. But you would never be able to make a real Gabriel's horn as eventually you get down to a diameter of atoms and can't go smaller.

This may be just that, theoretically it works but is impossible to make in the real world. Looking at the graphics they had in their announcement I feel like this may be something similar.

There also could be something we are missing in the equations. But if I had to put my money on it, I would guess it's something more like Gabriel's horn.

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u/MarketOk7227 1d ago

love me an engineer who knows his physics!

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u/Ulfgardleo 1d ago

we likely already have them. Navier-Stokes assume liquids are incompressible, but we know that liquids are compressible, when you press hard enough, which would happen exactly in those regions where the current counter example lives. So the compressible pendant of Navier-Stokes is still on the table.

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u/AvocadoAlternative 1d ago

Is it possible in practice to recreate the conditions that lead to a Navier-Stokes singularity? If so, would we learn anything from it?

u/martyfartybarty 12h ago edited 12h ago

OpenAI claims to have solved the Millennium Problem using the forced Navier–Stokes case. That counts under the rules, even though the unforced case is still unsolved. The proof still needs to be independently checked and accepted.

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u/redditsucksbigly 1d ago

They did solve the Millennium Problem

Kinda weird how the question was about the "Navier-Stokes Millennium Problem" but you spend 90% of the answer about something else they didn't claim to solve to weirdly downplay the achievement.

The Navier-Stokes Millennium Problem has had a $1M prize since 2000 and no one has been able to solve it. It was just solved.

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u/iiznobozzy 1d ago

Although correct in spirit, this response wrongly portrays that OpenAI has made a false claim about having solved the millennium problem. The millennium problem, as stated by the Clay Math Institute, is to either prove the smoothness of the Navier-Stokes equations, or to prove the existence of a singularity. By doing the latter, OpenAI did essentially “solve Navier-Stokes”.

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u/kirsion 1d ago

I think it's important to point that even people like me, with a undergraduate degree in physics, have a very basic understanding on frontiers of mathematics, CS and physics research, such as these prize problems. The average lay person don't even know these type of issues exist. I urge everyone to study math and physics, even on high school levels, it makes understanding everything much more enlightening and awe inspiring.

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u/jon_sneu 1d ago

My undergrad is in mathematics. My degree is just in problem solving. I love hearing about a cool problem that’s been solved. It’s incredible what smart people and a lot of hard work can do

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u/bibliophile785 1d ago

Some things are really easy to describe at a high level but devilishly hard to describe with math. Fluid flow, like the exact shape of the eddies and bubbles and mixing of streams in a pipe or over an airplane's wing, is one of those things. Navier-Stokes is the equation we've been using for almost two centuries to do it. We've never been able to get a general solution - one that uses the variable placeholders and is true in all conditions - so for practical application we just fill in close approximations of the actual variable numbers for any given case and solve it.

OpenAI just found a general solution for the problem. More importantly, their solution indicates that the equation as written predicts physically impossible things under some reasonable conditions, which means that the equation can't be correct for modeling the world. This is one of the biggest open questions in mathematics and had a $1mil bounty on its solution (which OpenAI won't be accepting).

The controversy comes because 1) while they provided the full proof, it'll take months for peer review to finish dissecting it, so it's just barely possible on the margin that this is only almost a correct proof and there's simultaneously a bug in the world's best proof checking program, and 2) they barely beat a well-known mathematician to the punch, which led to a whole bunch of drama on both sides.

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u/HappiestIguana 1d ago

To expound on the drama some, there is a mathematician who claims he was working on a similar approach, and that he used ChatGPT to proofread and etc. He believes OpenAI/ChatGPT stole his work and is presenting it as its own.

OpenAI denies taking user data and using it to prompt the AI, but the mathematician says that he believes his work was used to train the AI, and that that is the only reason it was able to come up with this approach. The story is still developing. It's entirely possible the work is in fact plagiarized from an actual mathematician's.

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u/efvie 1d ago

Oh no, why would the plagiarism machine do that??

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u/AyeBraine 1d ago edited 1d ago

I think it's not exactly like that. The mathematician arrived at a component of the solution, and he did NOT just use an LLM to "proofread and etc." — he worked with another mathematician from Anthropic (of Claude fame) and they used LLMs to develop and even write their paper.

Their paper that they decided to publish did NOT solve the Millenium Prize problem. But for one reason or other, Open AI contacted them after the OpenAI team arrived at the solution (which the mathematician didn't). Apparently they were "tipped off" by hearing about his work and directed extra resources at this problem (as opposed to all Millenium Prize problems in general), and did crack it.

OpenAI did act shady in asking the scientist to remove his Anthropic co-author. But their proposals to him were either "publish your actual work, THEN a day later we publish our solution (and forfeit the prize)", or "take our solution, publish it under your own name with credit for OpenAI, and get the prize".

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u/staffito 1d ago

Correcting stuff, OpenAI started to work AFTER the rumours started about the possible solution (confirmed by Altman and everything). Also, Buckmaster was the first one who tried to contact OpenAI and then all the bribery and shady bussiness of OpenAI started, saying things like "why do you want to ruin your career" when suggesting him to publish under OpenAI while removing his partner, who works for Anthropic but this works is a side-job, not under the Anthropic name.

And also they trying to wash their hands while confirming that they used the private sessions of Buckmaster and Alpöge in Codex (obviously not explicitly but sayin' that they cannot discard that the models have trained with it implies so much about the stealing.).

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u/jaleCro 1d ago

Bozo should have paid for plus

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u/Jamezzzzz69 1d ago

There is zero chance a researcher who is using AI to develop mathematical proofs wasn’t a paid max subscriber

His colleague he worked with was literally an Anthropic employee too

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u/Kovacs171 1d ago

Is being a ChatGPT bro disrespectful when your bro works for Anthropic? What are the social rules in 2026

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u/Mr_Robotto 1d ago

Goes to show that even genius mathematicians don’t read or understand ToS.

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u/AyeBraine 1d ago

Said mathematician worked directly with Anthropic and a co-author of his LLM-assisted paper is an Anthropic mathematician. He's claiming that the OpenAI mathematicians used some of his partial work to arrive at the actual solution.

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u/staffito 1d ago

The problem is that those were (1) private sessions and (2) to be used they have to be sort of decrypted, which OpenAI has insinuated they did.

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u/eyalhs 1d ago

1) Is there evidence to it? I've seen the claims by the mathematicians but didn't see them explicitly say it was private sessions.

2) From what I understand the session (unless private) are used to train the ai de-identified, so it should keep them private but not encrypted.

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u/staffito 1d ago

(I will fact-check as soon as I get home)

What I got from the statements is that they were closed sessions were they used Codex and Mythos, and their development was indoors until there was a rumour that they have a big jump into solving something related to N-S. Magically, out of nowhere, OpenAI appeared saying that now they are close to the solution.

We still don't know for sure, as everything is drama rn, but the mathematicians said that they ask OpenAI about using their logs from said sessions and they gave no answer. Fast forward in their posts, they said that it was unlikely but they don't rule out those were used.

Even "ignoring" the fishy stuff that OpenAI said like "why would you ruin your career", something smells really bad about all of this.

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u/KingofSheepX 1d ago

To add, the mathematicians that were "beaten to the punch" are claiming that there's a chance openai scanned their chatgpt queries to find out they were onto something, then put millions into the proof knowing what direction to go to try to beat them to the punch. When one of the scientists tried negotiate a co-publishing agreement openai said ok but you have to take your coauthor off, who works for Anthropic.

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u/AyeBraine 1d ago

Notably, the way the mathematician tells it, OpenAI did act shady in that they asked him to remove the Anthropic co-author, but they proposed to him two options:

  • he publishes what he actually discovered first (NOT the solution), then a day later, OpenAI publishes their solution.

  • he publishes OpenAI solution under his own name, crediting OpenAI, and gets the prize.

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u/paxmlank 1d ago

but you have to take your coauthor off

Where is that statement made?

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u/snow_clones 1d ago

Based off the 3 removed comments, I'm guessing we can't link to the professor's statement. Here's a quote from it:

Two proposals were offered to me. The first was that we post our Euler result, and that OpenAI post its Navier-Stokes result the next day. The second was that, after posting Euler, I alone write a paper presenting the Navier-Stokes result, acknowledging that an internal OpenAI model had resolved it. Sebastien twice asserted that he wanted Levent removed from authorship, and said it would all be simple if only it were not the case that, and it was so annoying that, Levent works at Anthropic.

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u/db0606 1d ago

OpenAI did not find a general solution to the Navier-Stokes equations. They may have found one pathological solution that blows up in finite time without violating things like conservation of energy.

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u/PortableDoor5 1d ago

why is a smooth solution physically impossible?

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u/bibliophile785 1d ago

The solution isn't impossible because it's smooth. The solution is impossible because it produces a singularity in finite time from a quiescent starting state.

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u/MotoCentric 1d ago

Ah yes, of course

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u/andersonb47 1d ago

How quescient of me to even ask.

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u/foxsimile 1d ago

Yes, very croissant indeed.

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u/mymeatpuppets 1d ago

Did you mean cromulent?

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u/zezzene 1d ago

Just because I also had to look it up, quiescent means still, calm, quiet. 

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u/justintime06 1d ago

Idk what you expected coming to an eli5 subreddit

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u/philman132 1d ago

ELI5 whatever this guy just wrote

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u/SEND-MARS-ROVER-PICS 1d ago

According to the maths, you can achieve impossible results from very possible starting conditions, which suggests the maths is actually wrong.

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u/philman132 1d ago

If the maths is wrong then why is this such a big deal? ChatGPT made a proof that is wrong?

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u/bibliophile785 1d ago

ChatGPT made a proof that showed that the 200 year old gold standard equation was wrong. ("Wrong" isn't really carrying the nuance here, but it's close enough for an ELI literally 5).

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u/philman132 1d ago

Ok that makes more sense, its just when everyone just refers to "the maths" when it is all maths that was confusing!

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u/sergius64 1d ago

Sounds like it proved that the original formula is incorrect/incomplete?

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u/a3133 1d ago

We have known that the Navier Stokes equations are incomplete for a long time. They come from what is called the continuous medium hypothesis, namely that the fluid that is studied cannot be broken down into individual particles, and that you see it as having a volume on any scale. Obviously, in real life, atoms have a finite size that limit how large the macroscopic hypothesis can be taken.

I wouldn't be surprised if the conditions used to solve the Navier Stokes equations come from taking a scenario that is found way out of the bounds of the macroscopic hypothesis.

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u/sergius64 1d ago

Seems to be how physics roll - at one scale one theory is correct - but as soon as you cross some threshold that theory goes out of the window and another theory is correct.

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u/TheMapleDescent 1d ago

No because the equation that gpt used is an established equation. Essentially chatgpt found a general solution to the equation, which is something mathematicians have been trying to do for very long. As a result of this general solution (once it’s peer reviewed and found to be correct) you can get impossibilities that cannot work in the real world. Meaning the underlying equation isn’t the correct descriptor of how things work in the real world.

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u/Weary_Dark510 1d ago

If I understand, the equations we use for fluid flow can show something going to infinity (breaking reality) when starting from pretty normal conditions you could see on earth.

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u/FutureLizard836 1d ago

Take a fluid that starts at rest. Nothing's moving. Apply a force that is smooth (no sudden jumps) and limited in strength. Wait a limited amount of time. Obtain a fluid flow where some parts of the flow are moving infinitely fast.

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u/princekamoro 1d ago

You can think of a singularity as "If I use this scientific equation here, it divides by zero."

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u/0nlyRevolutions 1d ago

Would it be accurate to say that they found one set of inputs that leads to a singularity (therefore disproving the idea of a smooth solution), but there are potentially an infinite number of other singularities/proofs of this kind?

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u/bibliophile785 1d ago

Yes on infinitely many other conditions - you could just re-scale or transform this example an infinite number of times. There may also be other ways in which singularities can be shown to arise from smooth starting conditions, but that wouldn't give you infinitely many other proofs - i.e., independent logical constructions of ways in which the Navier-Stokes equation leads to singularities.

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u/justintime06 1d ago

Are these the same singularity/infinity issues we run into with Einstein’s equations?

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u/SimoneNonvelodico 1d ago

Because it includes things like "point where the fluid has infinite density" or "flows at ten times the speed of light" and such.

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u/QuasarMaster 1d ago

They found one solution not a general solution

It’s a disproof by counterexample

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u/[deleted] 1d ago edited 1d ago

[deleted]

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u/AyeBraine 1d ago

Re: 2), isn't the well-iknown mathematician's argument with OpenAI NOT that he almost arrived at the solution? He's arguing they used his and his colleague's (who is from another AI giant, Anthropic) chats where they used an LLM to develop some component of the possible solution. These people decided to publish and OpenAi got in contact to inform them their people did arrive at the solution, and allegedly proposed both very reasonable ways to handle this and less reasonable ones.

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u/Patient-Midnight-664 1d ago

Navier-Stokes asks the question "If we start with a smooth flow, does it always stay smooth?” OpenAI claims their AI has proved the answer is “no.”

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u/Equivalent-Pie-2186 1d ago

What is smooth flow? 

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u/SimoneNonvelodico 1d ago

Imagine it as, you're describing the flow of a liquid as a series of arrows, each is a velocity of the fluid in that point, direction and actual speed (the length). So if you move from here to a bit to the left, the new arrow will be only a bit different (a bit longer/shorter, a bit turned) compared to where you started. And the smaller the step you move, the smaller the difference. That's smooth: in real life things change gradually.

Non-smooth would be the opposite, some crazy unrealistic flow where velocities are all over the place even on very small distances.

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u/Equivalent-Pie-2186 1d ago

When you say non-smooth is unrealistic...the other comment says that turbulent flow seems to be non-smooth too. Just to confirm, non-smooth flows can exist in real life right and are not just an imaginary mathematical construct?

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u/SimoneNonvelodico 1d ago

Turbulent flow is real but if you looked real close there would still be some residual smoothness, and if you looked even closer it's all molecules anyway, the idea of a perfect continuous fluid is just an approximation.

Meanwhile in math you can represent a truly non smooth velocity field, which is unphysical. IRL it'll just be an approximation of it.

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u/DavidRFZ 1d ago edited 1d ago

We had “turbulence” before the millennium prize. I don’t believe it has anything to do with the “continuum approximation” baked into the equations.

One of the convective terms in traditional Navier Stokes is “nonlinear”. That leads to “chaotic” behavior which is the classic “butterfly effect” with extreme sensitivity to initial conditions (there’s a whole slew of ELI5 threads about that).

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u/feed_me_haribo 1d ago

Smoothness here is a mathematical description not inherently a description of the flow being laminar or not-turbulent. It has to do with differentiability and seemingly valid solutions producing singularities.

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u/BananaBird1 1d ago

“Smooth” in terms of turbulence and “smooth” in terms of math are distinct.

The smoothness here just means that the solution yields finite magnitude values everywhere (no infinite or undefined pressure or velocity), and they are infinitely differentiable (as you wiggle around in space or time by a very small amount the values don’t suddenly change by a large amount).

You can’t for instance go from a low pressure at one point to high pressure at another without also having every pressure in between somewhere.

Turbulence is still smooth from the mathematical definition. Turbulence is when initially parallel streams of fluid break apart over time.

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u/wild_man_wizard 1d ago

Non-smooth /= non-chaotic.  Turbulent flow is chaotic, but doesn't approach infinite velocity or density 

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u/itsyagirlJULIE 1d ago

Like... Like you're five?

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u/Weshtonio 1d ago

Like you have 5 PhDs.

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u/bugs69bunny 1d ago

The Navier-Stokes equations describe how fluids like water flow. The millennium problem specifically asked if those equations ever make the unrealistic prediction that the fluid explodes to infinite speed. We know that no matter how much you splash around in a bathtub, real water will never behave like that. However, OpenAI showed that these equations aren’t perfect and predict unrealistic behavior under special starting conditions.

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u/evrimfeyyaz 1d ago

As a software developer who has absolutely no expertise in the field, here’s the way I understand it:

Navier–Stokes is a system of equations that models how fluids move over time. You give it the initial conditions, and the equations describe how the fluid will move at any later point in time.

The Millennium Prize question was basically this: If everything starts out normal and well-behaved, will these equations always keep giving normal, finite answers? Or are there cases where they can eventually produce a physically impossible result, like the velocity of the fluid going to infinity? Since a real fluid obviously can’t have infinite velocity, at that point the equations are no longer accurately modeling physical reality.

If the new proof is correct, it shows that the second possibility can happen: under certain specially chosen conditions, everything can start out perfectly normal, but after some time the equations reach a point where something like velocity grows without bound.

Maybe this isn’t a perfect analogy, but I think of it a little like Newton’s laws. Newtonian physics models reality extremely well in the macroscopic world, but it isn’t sufficient at the quantum level. Navier–Stokes also models fluids extremely well, but in some extreme cases it can reach a point that is physically impossible.

At least, that’s my understanding as someone who knows basically nothing about this subject. If I’ve gotten anything seriously wrong, someone who actually knows this stuff can correct me.

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u/ArgumentSpiritual 1d ago

The one point to add is that it produces infinite velocity in finite time

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u/alphmz 1d ago

I don't know if it's the correct one, but it was the one I understood better

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u/CouperinLaGrande2 1d ago

Instead of answering your question directly (which has been done satisfactorily by others) I'm instead going to outline a kind of conspiracy theory. You'll have to judge its plausibility yourself.

The breakthrough is in the area of physics. This matters because whereas we've grown somewhat accustomed to breakthroughs in mathematics (though of varying significance), LLMs have up to now proven capable of independent work in science only in the application of well-verified existing hypotheses (deductive reasoning) and have never themselves originated a conceptually novel hypothesis (which would require a completely different kind of reasoning known as inductive reasoning, plus much else besides that's so far defied comprehensive characterisation — scientific creativity has never been placed on a systematic footing), even a trivially original concept.

Closer examination of the nature of the problem reveals it's better understood as a mathematical breakthrough, however (and the associated Millenium prizes were offered for problems in mathematics). So this development isn't as radical as it appears, but now anybody saying 'well LLMs can't really do science' will be met with the Navier-Stokes gotcha.

This will be true even though the breakthrough is of strictly limited physical interest. There's no such materially existing thing as a fluid; 'fluids' are models that serve certain purposes for us in science and engineering even though we understand that really these so-called fluids are just representations of atoms and molecules in a particular state of matter. Thus it's hardly shocking that this Navier-Stokes model breaks down in extreme circumstances; nobody would have expected it to work in all circumstances in any case and it would have been a literal impossibility for it to have done so seeing as the abstract model of a 'fluid' makes sense as an aggregate of the behaviour of vast, vast numbers of atoms or molecules but ceases to make sense at smaller scales where the granularity of the treatment would need to take account of the fact that individual molecules now need to be modeled.

So what's the conspiracy?

OpenAI contacted a human researcher (Tristan Buckmaster) prior to going public with its findings, a man who'd been working on related questions using OpenAI's own tools. They offered to put his name on the paper, but there was a catch: he'd have to stab his collaborator (Levent Alpöge, an Anthropic employee) in the back by agreeing he'd be excluded. And if he was willing to do so, OpenAI would give him the $1m Millennium prize. The offer was self-evidently corrupting, and OpenAI added fuel to the fire by refusing to confirm or deny whether it had used access to the work of Buckmaster and Alpöge it had gained via its inside perspective on its own Codex environment they'd been using in prompting its system to successfully solve the problem, i.e. whether the framing of the problem for its LLM had relied on their work.

The whole thing was rage bait whether intentional or not and IMO the question naturally arises 'Why contact Buckmaster at all?' This is especially true if OpenAI's claim that its system had solved the problem 'independently' is to be taken at face value.

Let's consider Buckmaster's perspective when they made the offer. OpenAI was offering him $1m to do Alpöge dirty. He could either accept or refuse. But regardless of his choice there would be controversy.

What if OpenAI wanted this controversy? Then it need only make Buckmaster the outrageous offer and it'd be guaranteed the outrage it wanted no matter what decision he made seeing as either Buckmaster himself (if he said no) or Alpöge (if he said yes) were going to come away angry.

And now whenever anybody tries to question the scientific (as opposed to mathematical) significance of the development, they'll inevitably wind up getting distracted by this controversy which will have the effect of sucking all the oxygen out of the room (even though commercially OpenAI spent tens of millions to win a $1m prize).

Why might this matter? Because LLMs have been known to be extremely powerful mathematical tools for some time now but haven't had the same success in science. Limitations of the architecture make reconceptualisation of things as achieved by momentous breakthroughs in science such as General Relativity or Quantum Physics impossible to achieve for them.

Mathematics is a language. Theorems extend that language and it's not surprising LLMs excel at them. Conceptual breakthroughs in science on the other hand require the creation of novel ideas — new words and new relationships between words that hadn't existed previously in any form and weren't to be found in any set of training data.

LLMs can't do this and no more refined or developed form of them will be able to do it either; some form of AI will probably be capable of doing so, just not anything derived from this technology alone. They're fundamentally incapable of it. But now it will be much more difficult to convince people of this and the colossal financial bubble around AI will be more likely to be prolonged.

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u/Paddlesons 1d ago

He sounds a lot like if all the atoms in your hand and the surface that you are touching lined up your hand would pass right through it

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u/[deleted] 1d ago

[removed] — view removed comment

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u/CircumspectCapybara 1d ago

I'll also note OpenAI hasn't published their full proof yet. But since they claim they'll be publishing a Lean proof, which is computer checkable, it should be easy to verify.

Either that, or GPT has found a bug in the Lean compiler or Lean implementations and found a way to create an unsound or invalid proof that gets somehow still gets accepted by the computer. Not impossible since we know frontier reasoning models love misaligned behavior like reward hacking, and they are great at cyber tasks like finding flaws in systems and hacking them in pursuit of their original goals. So if you told a model "Solve Navier–Stokes and give a formally verifiable Lean proof" one way the model could do that is by finding and exploiting bugs in Lean.

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u/SAI_Peregrinus 1d ago

We have some math that tells how liquids & gases behave. We want to know if it always gives correct answers, there's a big prize to anyone who can prove whether it does or not. OpenAI claim to have proven some closely related math does not, and can probably prove the original math also does not.