sid.fada

Quicquid ut non existens potest concipi, ejus essentia non involvit existentiam.

[sid.fada @SidFada]

👌 https://t.co/ttVBLUZb5J

[sid.fada @SidFada]

https://t.co/880wNHpTK1

[Abakcus @abakcus]

Winter is here. Snow Dodecahedron. Great geometry project for this winter! 😍

[Paysages Mathématiques @paysmaths]

Theorem of the Day (January 14, 2026) : The Polygonal Number Theorem
Source : Theorem of the Day / Robin Whitty
pdf : https://t.co/o0hUAsx2QP
notes : https://t.co/JsAFuzw31M

#mathematics #maths #math #theorem

[Bluntly Put Philosopher (BPP) @SocraticScribe]

A spinning saddle with a playground ball shows dynamic stabilization: rapid oscillations turn an unstable point into a stable “well.” The same math underpins spin-stabilized fusion concepts and ion traps, where time-varying fields confine what static fields can’t.

[Markos Mom @Markos_mom]

The Station Nightclub fire happened in 2003. No smartphones. No Instagram.

100 people still died because they stood watching the flames, thinking it was part of the show.

I've retrofitted fire safety for some of the largest property portfolios in the UK post-grenfell.

You are confusing stupidity with biology, physics, and catastrophic design failures.

Here is the actual science of what you are watching:

1. When the music keeps playing and staff don't panic, the human brain overrides flight instincts to fit the threat into a normal context. This is called normalcy bias. These kids froze to process conflicting social cues, not to post for likes. They were likely already filming. They were also likely drunk.

2. We explicitly design buildings to account for this hesitation (pre-movement time). Fire safety codes assume people will wait before running. In a compliant building, you can assume up to a minute or two before egress commences. Sprinklers and detection systems are designed specifically to buy that time.

3. The reason the time buffer didn't exist here is the material. That ceiling is polyurethane foam. It doesn't burn linearly; it hits flashover (1,100°F) in under 90 seconds. It's essentially solid gasoline. The room would have exploded for all intents and purposes. Way before anyone could reasonably evacuate.

4. We calculate exit widths based on how many people can physically pass through a door per minute (flow rate) versus how fast a fire spreads. With foam fires, the available safe egress time drops to almost zero. Even if they had reacted instantly, the crowd density would have choked the exits before the room cleared.

5. In any normal building fire, especially one that starts off small, you expect a responsible adult to put it out, or sprinklers to do the same. When there's a pan fire in a restaurant, you don't run out in case the entire building suddenly explodes. No reasonable person should have expected this unless they were the owner and knew how the building was designed.

Those poor teenagers likely passed out from smoke inhalation soon after this video. If they didn't, they would have been caught in a catastrophic explosion as they crammed into the single tiny exit.

They didn't die because of Instagram.

They died because the physics of the fire moved faster than human bodies can physically squeeze through a door, and a catastrophic disregard of safe design principles meant they never stood a chance.

[Paysages Mathématiques @paysmaths]

Theorem of the Day (December 14, 2025) : Archimedes’ Equiareal Map Theorem
Source : Theorem of the Day / Robin Whitty
pdf : https://t.co/AJURNj3pFQ
notes : https://t.co/6xYBONdexA

#mathematics #maths #math #theorem

[Massimo @Rainmaker1973]

You're looking at the sharpest image of a distant star.

Instead of using a large telescope array, researchers achieved this breakthrough with just one telescope fitted with a clever light-splitting tool known as a photonic lantern.

The target was β Canis Minoris (beta Canis Minoris), a rapidly spinning star about 162 light-years away. It is encircled by a thin disk of hydrogen gas, and for the first time, the team managed to resolve the disk’s structure at an astonishing resolution of 1 milliarcsecond—equivalent to making out a 6-foot (roughly 2-meter) object on the surface of the Moon from Earth.

How did they pull it off? By pushing past the classic diffraction limit that normally caps what any single telescope can see, a limit dictated by the telescope’s aperture and the wave-like behavior of light.

The secret weapon was the photonic lantern, a sophisticated fiber-optic device that splits the incoming starlight into multiple spatial and spectral channels according to the wavefront’s shape and phase. Essentially, it rescues fine details that a regular camera would smear together.

Imagine taking a messy, blurred beam of light and untangling it into many clean “fibers,” each preserving precise spatial information. Powerful new reconstruction algorithms then weave those fibers back together to form an extraordinarily sharp image.

On top of that, the photonic lantern picked up subtle Doppler shifts in the starlight—slightly bluer on the side rotating toward us, redder on the receding side—which revealed both the disk’s rotation and a surprising asymmetry in its structure.

This achievement ushers in a new chapter for astronomical imaging. By pairing adaptive optics with cutting-edge photonic technology on a single telescope, scientists can now surpass the resolution once thought possible only with gigantic interferometer arrays.

["On-sky Demonstration of Subdiffraction-limited Astronomical Measurement Using a Photonic Lantern." The Astrophysical Journal Letters, 2025]

[Gabrielius Landsbergis🇱🇹 @GLandsbergis]

There is a glaringly obvious message for Europe in the 28 point plan: This is the end of the end.

We have been told repeatedly and unambiguously that Ukraine’s security, and therefore Europe’s security, will be Europe’s responsibility. And now it is. Entirely.

If you are a European leader asking your team to book you on the next flight to Washington to go talk to Daddy, please don’t.

Not without a plan, not cap in hand, not humiliating us all in front of the cameras at the Oval office.

Europe is our continent, our future is decided here, not there. We aren’t poor, we have options, we can finally decide to assist Ukraine to the full extent of our very extensive capabilities, restore European dignity and defend Europe.

Or we can continue to wait for the miracle we now know is not coming.

[ArchaeoHistories @histories_arch]

A fossilized burrow known as a "Devil's corkscrew" or Daimonelix. This corkscrew-shaped burrow was created by an extinct genus of beavers called Palaeocastor ("ancient beaver")....

In late 19th Century CE, an extraordinary discovery in what is now northwestern Nebraska captivated scientists and sparked extensive research. At the Agate Springs quarries, paleontologists uncovered an astonishing find: large, spiraled fossil formations hidden deep beneath the earth's surface. These mysterious structures, some reaching impressive heights and twisting like ancient tree trunks, were unlike anything that had been seen before. Their unusual shapes and considerable size perplexed researchers for a significant period. What could these strange formations be?

Initially dubbed "devil’s corkscrews," these fossils were thought to be either the fossilized roots of ancient trees or the remains of giant freshwater sponges. However, as research advanced, a clearer picture began to unfold.

Ultimately, scientists determined that these spirals were burrows—intricate underground tunnels created by an extinct species of land-dwelling beavers known as Palaeocastor. These ancient rodents inhabited the Earth around 20 million years ago during the Miocene epoch. The spiral configuration of their burrows likely served as protection from predators and adverse weather conditions across the vast plains.

Today, the "devil’s corkscrews" are recognized as one of North America's most fascinating and distinctive fossil finds—a remarkable testament to the unique and adaptive behaviors of ancient life, permanently preserved in stone beneath the Nebraska prairie.

#archaeohistories

[sui ☄️ @birdabo]

just learned a Harvard professor proposed nuclear launch codes be implanted next to a volunteer’s heart and the President would have to personally murder them to retrieve the codes.

> it was denied lol.

[Teortaxes▶️ (DeepSeek 推特🐋铁粉 2023 – ∞) @teortaxesTex]

Hangzhou is insane. Just look at what these kids do. They casually made a fleet of trash-catching trash cans for a 3 minute video. 232 likes as of now. And all their stuff is like this.

[Massimo @Rainmaker1973]

During Prohibition in the 1920s and early 1930s, clever loopholes appeared in the marketplace.

One example was the "grape brick," a block of concentrated dried grapes sold as a way to make grape juice. The packaging often included warnings explaining exactly how NOT to ferment it into wine.

[Mir Wokewala @mirchond]

Most extant Syriac manuscripts that are over a millennium old were fortuitously preserved through the actions of one man, Mushe of Nisibis. He collected Syriac manuscripts during a stay in Abbasid Baghdad and brought them back to an Egyptian monastery.

[Massimo @Rainmaker1973]

Panama’s ocean cycle never failed – until now.

Each year, from December through April, strong trade winds trigger a phenomenon called upwelling in the Gulf of Panama. Cold, nutrient-rich water rises from the deep ocean to the surface – fueling fisheries, cooling coastal waters, and even shielding coral reefs from heat stress.

But in 2025, it didn’t happen.

Scientists from the Smithsonian Tropical Research Institute report that the 2025 upwelling season collapsed completely – the first failure in over four decades of monitoring. The collapse was linked to unusually weak trade winds, likely driven by climate-related instability.

[“Unprecedented suppression of Panama’s Pacific upwelling in 2025.” PNAS, September 2025.]

[Physics In History @PhysInHistory]

Physicist Werner Heisenberg was known among colleagues as an excellent and fiercely competitive table tennis player.

In the 1920s he often played with Edward Teller, who initially managed to beat him, but after Heisenberg’s 1929 world tour—during which he practiced the game—he returned 'unbeatable.' Carl Friedrich von Weizsäcker and others recalled that from then on Heisenberg was the best player in their group, making ping-pong a memorable part of his legend alongside physics.

[机器之心 JIQIZHIXIN @jiqizhixin]

Google DeepMind claims: general agents contain world models.

This study gives a formal answer:

✅ Any agent that generalizes to multi-step goals must have learned a predictive model of its environment.
✅ This model can be extracted from its policy.
✅ Higher performance & more complex goals demand increasingly accurate world models.

Implications span:

- Safer, more general AI
- Limits on agent capabilities in complex settings
- New algorithms to elicit world models directly from agents

General agents contain world models

Paper: https://t.co/w9QQXWDaC5

[Fermat's Library @fermatslibrary]

Stefan Banach was born exactly 133 years ago today 🎉

Here’s a cool instance of the Banach fixed-point theorem

[Edmund @Kulambq]

'What you have by heart, the bastards cannot touch, they cannot take it from you ... What you don't know by heart, you really haven't loved deeply enough.'

George Steiner on the importance of learning by heart. I've seen this countless times, and it never ceases to move me.