Netsu🇺🇦

• symbolic💡structural 🇺🇦 •
▓▒░ семантичний підмурівок архітектоніки значення
~ dreams are not my own ~

[Netsu🇺🇦 @Pitometsu]

If live gives you coproducts, make free monad.

[Guillaume Claret 🐻‍❄️ @guillaumeclaret]

@kostascrypto Nice for the list of real examples! Here is a diagram I use, saying that security should combine different angles

Some hopes for better FV: developing more tooling to extend the verified scope, and backward compatibility proofs to keep the "experience" of battle-tested solutions

[lotz @lotz84_]

型≠集合なのは
```
data Fix f = Fix (f (Fix f))
data T a = T ((a -> Bool) -> Bool)
type P = Fix T
```
とすると P と T P は同型だが、
もしPが集合だと仮定すると濃度が
|P| ≠ |TP| = 2^(2^|P|)
となり矛盾。
（これは2階型付きラムダ計算でも工夫すれば示せる）
https://t.co/TDwSJDb3fK

[Netsu🇺🇦 @Pitometsu]

https://t.co/CDgCRlmHb6

[Andrii Sybiha 🇺🇦 @andrii_sybiha]

No good news for the Russians.

By refusing President Zelenskyy’s offer for direct peace talks, Putin lost his chance to get out of his failed war.

Things will only get worse for Russia. Battlefield losses will continue to grow. Failures will get more humiliating.

The economy will plunge deeper into recession. More jobs will be lost, taxes will be growing, and inflation will hit those most vulnerable.

There are already no safe places in Russia that can be exempt from Ukraine’s long-range sanctions. But their intensity will continue to grow.

The international pressure will not ease. It will only get stronger. Including the use of frozen assets, travel bans, and inevitable accountability for crimes.

All of this because the fanatic in the Kremlin wants to keep in power at any cost and is ready to sacrifice his country’s future and kill millions of people for his insane delusions.

All of this because he doesn’t want to admit a simple truth: he will never achieve his goals on the battlefield and he better abandon his delusional hopes of Ukraine collapsing soon, support from its partners waning, or pressure on Russia easing.

Russia will still have to accept a diplomatic solution but the terms will be far worse.

Putin’s refusal of peace should lead to a significant increase in international pressure on Russia and support for Ukraine.

[auonsson @auonsson]

There is a constellation of Russian satellites broadcasting an interfering signal on GPS/GNSS frequencies all across Europe.

It arrives about once a month, usually weekdays office hours CET since 2019.

All from a Zach Clemens et al article. Nb, intent is not proven.

[五十川 十一 @11_50iil]

遅刻が確定した模様😅

[Netsu🇺🇦 @Pitometsu]

@VictorTaelin @VictorTaelin what if linear terms can be handled more effectively? E.g. term (or sub-term) that consume all the free variables, and contains only linear subexpressions -- has no weakening. Would it worth to make weakening explicit and just a special case of linear consumption?

[undefined behavior @undebeha]

okay right sure so the exterior algebra is obviously* a kind of geometric algebra with a degenerate metric. if we focus on defining the convolution for the geometric product, we have to switch to a symmetric set difference and our bounds of integration are instead the whole pseudoscalar basis.

with this change we can pass in all sorts of convolution kernels to generate different sorts of geometric algebras including the exterior algebra or a generic vector geometric algebra

----------------------------

*"obvious" is used here in the mathematical sense as a synonym for "unexpected"

[undefined behavior @undebeha]

evil haskell tip: make the following type classes so you can write coefficients in front of your polynomials more easily

[lotz @lotz84_]

実はコルーチンはフリーモナドトランスフォーマーと同型になる
```
data FreeF f a b = Pure a | Free (f b)
newtype FreeT f m a = FreeT {
runFreeT :: m (FreeF f a (FreeT f m a))
}
```
Either の定義が
data Either a b = Left a | Right b
であることを思い出せば対応がわかる✍️

[José A. Alonso @Jose_A_Alonso]

A formally verified library of mathematical finance in Lean 4. ~ Raphael Coelho. https://t.co/m1mA0ZXjf9 #LeanProver #ITP

[Stepan | squads.xyz @SimkinStepan]

Formal verification is indeed the way.

A few years ago I reached out to @NotDeGhost asking him if he wanted to do the first formal verification for a Solana program. Luckily he said yes and got it done in 4 months. Since then all Squads programs have gone through that process multiple times.

Fast forward to today, we now also have Certora and many of the core ecosystem programs formally verified.

The biggest issue with FV is that it takes time and is very expensive. While the AI security apocalypse is stressful, it is also obvious that LLMs will help us drastically compress the time and cost it takes to prove the mathematical integrity of onchain codebases. Maybe that will be the silver lining of it all.

[Slava 🇺🇦 @Heroiam_Slava]

In Crimea people are preparing for the liberation from Russian occupation.

[Volodymyr Zelenskyy / Володимир Зеленський @ZelenskyyUa]

Open Letter
To the President of the Russian Federation
From the President of Ukraine

When you came to power in Russia more than 26 years ago, many people in Ukraine viewed you positively. That is how it was. But that is now in the past.
Now, the overwhelming majority of Ukrainians view it positively that our long-range drones paid a visit to the opening of your forum in St. Petersburg, covering a distance of more than 1,000 kilometers. As you know very well, that distance is not the limit of our capabilities.

[lotz @lotz84_]

ラムダ計算の双対を継続モナドのクライスリ圏で構築した研究👀
値の双対は継続。ラムダ抽象と関数適用の双対もある（カリー化に対応して直積ではなく直和 Either が出る）。余関数を用いるとエラー処理やバックトラッキングを実装できる✍️
／
"The Duality of λ-Abstraction"
https://t.co/AJrBsiLVQG

[OSINTtechnical @Osinttechnical]

Footage of the Russian Navy Baltic Sea Fleet corvette Boikiy burning in its Kronstadt drydock after a Ukrainian drone strike yesterday.

[Thomas van Linge @ThomasVLinge]

Ukraine 🇺🇦: video published today showing a Ukrainian ambulance in the city of Kherson being deliberately hit by a Russian drone, circling above.

[Robin Hanson @robinhanson]

"Dijkstra said … Programming is not a craft. It is closer to mathematics than to carpentry, and the moment you treat it as a craft, you guarantee that the software you produce will be full of the kind of bugs that craftsmanship cannot catch. The fix, in his view, was to teach programming the way mathematics is taught. You should be able to prove your program correct before you run it."

Don't we have a half century of experience showing he was just wrong?

[Kraut @The_Davos_Man]

Ukraine is winning. That's why MAGA is trying to switch sides now.