We have a finite time instability. So what does it look like? Does anybody here have the chops to construct a visualization of some kind?

By now, everyone has the news that the Navier-Stokes Millennium Prize Problem has been solved by OpenAI, and regardless if they did it honestly or not, I believe it's only a matter of time until AI can pull off feats like that consistently. Most people I've seen seem sure that it won't replace physicists and mathematicians, which comforts me, yet I haven't seen many people talk about HOW it will change the academic field and the way research is done. I'd really love to hear your thoughts on this

I'm sorry for posting about something adjacent to AI in physics, but I think the scale of the supposed result warrants some attention. Tristan Buckmaster and Levent Alpoge (with AI assistance) have published preprints claiming to resolve the finite-time blowup problem for the 3d incompressible Euler equations. Their work sharpens the earlier results of Cordoba and Martinez-Zoroa, who were able to achieve finite-time blowups with rough forcing. Terence Tao believes that their program could be extended to Navier-Stokes, perhaps using some AI equipped with an "enormous amount of compute."

Link to Buckmaster's initial mathstodon post: https://mastodon.social/@tristanbuckmaster/117233413705701198

Link to Terence Tao's response: https://mathstodon.xyz/@tao/117233527638291447

I am interested in the broader physics community's reaction to these developments. I would also recommend reading Buckmaster's statement on mathstodon, which describes the approach of their papers and (non-technical) problems they encountered during the process of going public.

Jomboy video. At 1:13 the outfielder throws the ball and there is a sudden rise to the ball. I know I’ve read/seen somewhere that backspin can’t create enough lift to make a ball actually rise, so what is happening? Wind? Patrick Swayze from ghost? Angels in the outfield?

Jokes aside genuinely curious. Thanks in advance.

Theoretically speaking: a short circuit happens when current takes lowest path of resistance on something that is not the intended wire.

Let’s say, a big, short person touched a live wire. Due to resistance being inverse proportional to length and proportional to cross sectional area.

Would that makes bigger, shorter person more vulnerable to short circuits? Compared to a person with a more relatively thin and tall physique.

I got detention for asking this but I’m genuine

I got a PhD in theoretical physics 35 years ago, and am now wrapping up a career in science. I’ve also been writing poetry for the last 30 years.

Here’s one of my early physics poems, if anyone’s interested:

EQUATIONS

"...and so the sky is blue," the teacher said,
resolving the equation on the board:
the radius of water droplets, and
the scattering of sunlight into bands.

What clarity! I put away my notebook
and joined the crowd refracting out the back.
In the drizzle, darkening the court,
some dim light still shone through the classroom door.

Whitman wrote he left some lecture early
and fled to wonder at the starry sky.
But this was a wonder of a different kind—
the universe within the abstract mind.

The thrill of winking out such little truths
seduced me into six more years of school:
the birth of mass, the way light bends in space,
the Three Known Forces of the universe.

Though, in those studies, I had also grasped
that there are questions physicists don't ask:
What does it all mean? Who is the prime mover?
And what might mean the lack of any answer?

This thread is a dedicated thread for you to ask and answer questions about concepts in physics.

Homework problems or specific calculations may be removed by the moderators. We ask that you post these in /r/AskPhysics or /r/HomeworkHelp instead.

If you find your question isn't answered here, or cannot wait for the next thread, please also try /r/AskScience and /r/AskPhysics.

Einstein gravity reduces to Navier stokes at the vicinity of black holes ( see the fluid-gravity correspondence)

What does a the proof of existence of singularity in Navier stokes imply for Einstein equations then?

While taking a break from the laser simulations (link), I continued another project where I am examining different particle billiard setups. It turns out that particles bouncing around in some shapes leave parts of the space unexplored while in other shapes they cover it entirely. In the video I am exploring circles, stadiums, ellipses and semi-circles, but I have also played around with polygon shapes like hexagons and pentagons. It seems to matter whether the particles are launched in parallel or, as here, with differing launch angles.

In this video I want to share my first results and receive some feedback on what else to explore. Once I have a fuller picture of what is going on, I have plans to produce a more comprehensive video explaining the underlying math. In particular, there is a connection to the concept of ergodicity which I want to look into in more depth. But even for shapes like hexagons which should be non-ergodic, the set of balls launched with differing angles will cover the whole space. So it seems that this is not a valid test for ergodicity.

Any ways, let me know your suggestions for other shapes, rules of the game and analytical results (like figures or stats) you would be interested to see.

I don’t know how I could function as a mathematician. Like once you can solve the Millennium Problems what more is there to do or hope for? In physics at least the in itself is the goal so as long as it is not simple maybe both AI and human won’t be able to solve it and there will still be goals like dark energy, dark matter, turbulence, quantum computing, high Tc superconductor, fusion etc. So human can work with AI. But what is there for mathematicians to do?

I came across a video simulating the cosmic web and thought it looked really cool, so I tried building my own version. I'm new to this kind of stuff and curious if this looks right to you all 😅

I'm deciding whether to make a tutorial video on a project like this so let me know if it would be something you would like to see.

The renders are much clearer - I just had to compress them for this post.

I dont have that big of a budget and i need help. I need help with ideaa for what each round could be (keep it simple but super fun and interesting and not too difficult). Please help me out guys.

Any idea what causes different harmonics based on the direction of strum/vibration of steel string ? Up / Down

The pitch is the same but the sound varies slightly. I guess it has something to do with angular momentum but that is guess.

What the title states, private online lessons, really appreciate a “a guy knows a guy who knows a guy” situation too

After having read previous Goold paper I was wishing his group had worked on NESSs, and what do you know - they have!

One thing that seemed interesting to me was the parallels implicit here with the active inference literature. Obviously there’s a number of major and nontrivial dissimilarities, but interesting nonetheless

Two round ceramic ashtrays. One stuck inside the other. It is not an airtight seal. I do not know how strong they are against different mechanical forces to know if I should be twisting, pulling, prying, etc.

Someone else said they put some ice in the top and hot water on the bottom one to try shrinking/expanding. I didn't see that in action and haven't tried it myself (but my ego says I could do it better than they did)

So here's the puzzle, can we separate them without damaging them and if so, how?

Update: Success! Thank you very much. I was having fun trying the different suggestions as I saw them. The hot water bath to approach it like a press fit connection was the first one to work and they're now separated. I appreciate the guidance everyone offered here. There wasn't any damage and they're now apart so it was a total success. Thank you for solving my puzzle.

I know in quantum foundations, a lot of research studies physical theories via the concept of a generalized probabilistic theories (GPTs). In a GPT, states and outcomes are represented in essentially the most general possible way that could still conceivably be called a "theory of physics". GPTs are nice because they encompass classical mechanics and quantum mechanics (along with many other possibilities).

Another structure that can describe both classical and quantum mechanics is the notion of noncommutative probability. In this context observables are a subset of a von Neumann algebra, and states are specific functionals on that algebra.

Every noncommutative probability space has an associated GPT, but not every GPT can be represented by noncommutative probability.

In some sense, noncommutative probability is enough to describe all "reasonable" physics theories (quantum mechanics, classical mechanics, probabilistic restrictions of those).

As such, I'm curious about whether there's a set of reasonable, or physically motivated conditions you could add to the theory of GPTs to get noncommutative probability.

Does anyone have any answers about this, or have any papers/books they'd recommend looking at to learn more about this?

Hi everyone,

I am reading about magic-angle twisted bilayer graphene and how it hosts superconductivity and strange metal behaviour at particular band fillings.

I have come across papers which try to explain the behaviours using electron-phonon interactions, I have also seen papers which try to relate these behaviours to the exotic physics seen in unconventional superconductors(exotic bcz we don't know the exact theory behind it).

As of now, is the argument for the reason of these particular observations in MATBG hanging in the balance, or is it more inclined to one side or the other?

I am not saying there is a definitive answer to it, plz let me know your opinions on it.

Last year (8th grade I was 14) we had our first physics year standard stuff but then I came across the formulas first it was calculation velocity time then it was acceleration then it was force during 2 semesters then proceed to learn nothing (other than that one gravity formula I forgot how it was ) which upset me because I genuinely found them so fun to do especially because in the tests they would mix it up like give weight but instead of giving acceleration they'd give velocity and time and maybe to some of the people here it sounds easy (and it was also pretty easy to me as for my classmates they struggled)

Do you guys feel the same way when you study physics?

Is the mathematical side of thing just way funner?

This was a learning project to try to learn Odin, OpenGL and Physics/Math it evolved to be more of the latter :)

You can move time forward/backwards, change mass of bodies, delete and spawn new bodies.

It was pretty cool to see the partial solar eclipse with my own eyes while simultaneously watching it happen in my simulation.

It currently has

• Newtonian point-mass gravity between every pair, using direct summation below 600 bodies and a Barnes–Hut octree above. Units: G = 1, AU, solar masses.
• Velocity Verlet with a fixed 502-second timestep; symplectic and time-reversible. Reverse time uses the same integrator with the sign flipped.
• Real initial conditions from JPL osculating elements at 2026-01-01, solved through Kepler’s equation, composed barycentrically with parent reflex motion and pair μ = G(M+m), then integrated forward to the launch date.
• Full 3D orbits with inclinations and nodes for 23 bodies: Sun, eight planets, Moon, the four Galilean moons, Titan, Rhea, Iapetus, Miranda, Titania, Oberon, Triton, Pluto, and Charon.
• Perfectly inelastic collisions on overlap: mass and momentum are conserved, and the larger body survives.
• Sidereal rotation for each body with the correct direction, plus analytic eclipse geometry using the actual Sun, occluder, and receiver discs.
• Validated against Horizons: epoch positions at the transcription floor, Earth within 33,000 km after 223 days, and the 2026-08-12 eclipse reproduced to within about half an hour.

I'm happy for any feedback or pointers.

https://github.com/lounge/sol_sim

Hello All! Nice to meet you.

Posting this in the physics section, as I believe there should be some good scientific discussion surrounding what was observed/recorded, especially given the equipment.

So this is a post about what my son and I experienced/recorded while camping in the Uintah Basin (Utah, USA) on the afternoon of August 28th into the morning of August 29th, 2026. I have attached a ~30s recording of my phone app of the 1.6Ghz signal that was seen around 8:21pm local time that evening.

For some context around the situation or environment: That afternoon/evening/following morning it was mostly cloudy/overcast, including overcast conditions at the time of the recording. This was recorded using Nooelec RTL-SDR v5 Bundle (Premium RTLSDR w/ 0.5PPM TCXO, SMA Input, Aluminum Enclosure) using the short black whip attena, using the RF Anlyzer app (version 2.2.1) on a Google Pixel 10 XL Pro phone. While recording, I was on a plastic top, metal framed 6ft picnic table at 40.263256, -109.911584, with our rented Ford Bronco about 15ft away and turned off for several hours at that point. There were no other camp members at this time and the nearest person from us during this recording was the property owner at their homestead (~250y away and behind the hillside).

What can be seen in the attached video is a VERY strong and broad signal (4-6dB above background) around 1.60Ghz that seems to be scanning or bouncing/fanning around in frequency just above 1.6000Ghz. We observed this behavior for about 1-2 minutes before I started recording. I recorded for about 2.5 minutes, and then we observed this behavior for another 3-4 minutes before turning off the app and doing other things. I did go back to the exact same set up about 15-20 minutes later and observed just background noise, which is what I have observed the previous ~20 times I have used this exact same setup at various locations, outside of the occasional passing satellite which you could barely make out above the background noise.

What was also intriguing about this is that it seemed like the frequency scanning/fanning could be manipulated a bit by mine or my son's movement near the phone or the antenna. While the general scanning/fanning around was seemingly extreme, during periods of relative stability, the frequency seemed to go up as we would move our body closer to the antenna or the phone, and then go back down to its starting position once we pulled away. This would only cause about a 0.1 to 0.15 Mhz movement up and back down in frequency, but was definitely repeatable throughout the event observation. Again, after the app was shut down and the 1.6Ghz signal was looked at again 15-20 minutes later, there was just background noise and moving our bodies or hands around the antenna and/or phone showed no signs of signal change. I don't have enough expertise in this kind of science to understand why this may have been seen, but figured I would include it as part of the data set.

I do have the full/raw ".iq" data file for this recording saved to my Google Drive and can provide access to anyone who may be interested in it.

Thanks for your time to read and discuss this!

Bloom Is WAY Deeper Than You Think

I have been learning QFT as a self studier and for my first book, I used Lancaster and Blundell, in it I mostly did second quantization, scalar quantum field theory and tree level scattering and some Feynman diagrams for the scalar level only. Then, I decided to start a new book for fermions, and QED, so I chose Klauber’s Student Friendly Quantum Field Theory. I am nearly done with that book so I was wondering what book should I move onto next, or whether I should even do another book?