Yuri Sulyma

I think the statement is that the functor 𝕎: CRing → CRing is given by Spec of the ring of symmetric functions

The Action of Young Subgroups on the Partition Complex We study the restrictions, the strict fixed points, and the strict quotients of the partition complex $|Π_n|$, which is the $Σ_n$-space attached to the poset of proper nontrivial partitions of the set...

2/ I would like to understand genuine ∑_n-equivariant homotopy theory, in particular this paper arxiv.org/abs/1801.01491. At one point I aspired to compute the ∑_n-slice filtration of ∑^∞ |∏_n| using their paper. However, that project is too ambitious/time-consuming now that I've left math.

I wish I knew more about them for a few reasons:

1) I frequently need to manipulate identities in 𝛌-rings, and Young tableaux give a conceptual explanation of the change-of-basis formulas between the different families of operations (in the p-typical context I need both δ_n and θ_n)

you are there now, go dance in the street

octillery with four sorries shooting out of its mouth

klang with grind all around its gear teeth

did I ever post my Lean tactic pokémon

H2 Meetup. A modern web event. Speaker: Yuri Sulyma Thursday Oct 9th, 6-9pm. 366 Adelaide St W, Suite 500, Toronto

I'll be presenting Liqvid tonight at @h2_meetup
pre-Remix Jam!

There's a compelling argument (Hesselholt-Pstragowski's Dirac geometry, the even filtration) for indexing homotopy groups by half-integers, so that π₂ becomes π₁ and π₁ becomes π_{1/2}.

Mathematicians are bringing counting into the 21st century. www.quantamagazine.org/new-math-rev...

ICE is Eating the Soul of America Four things that show ICE increasingly considers itself outside the law

New numbers show ICE is devouring US law enforcement: 1 in 5 US marshals, 1 in 5 FBI agents, half of all DEA agents, and over two-thirds of all ATF agents are now assigned to ICE enforcement. These are agencies with critical jobs they're now NOT doing.

www.doomsdayscenario.co/p/ice-is-eat...

Aqua in Edmonton!

Search LibGen, the Pirated-Books Database That Meta Used to Train AI Millions of books and scientific papers are captured in the collection’s current iteration.

Just a reminder to check for your name in this list of books that OpenAI trained from. If your name is there, they probably owe you several thousand dollars.

OpenAI cried that if everyone eligible author files, the company will go bankrupt, so I'm alerting every author I have ever spoken to.

Now I'm going to throw you in the thick of the definition of a polynomial. But stay with me! I want you to start by taking out a piece of paper and literally copying down the definition (the entire next paragraph), character for character, as one would type out a program from scratch. This is not an idle exercise. Taking notes by hand uses a part of your brain that both helps you remember what you wrote, and helps you read it closely. Each individual word and symbol of a mathematical definition affects the concept being defined, so it's important to parse everything slowly. Definition 2.1. A single variable polynomial with real coefficients is a function f that takes a real number as input, produces a real number as output, and has the form f(x) = a₀ + a₁ x + a₂ x² + ... + a_n x^n where the a_i are real numbers. The a_i are called *coefficients* of f. The *degree* of the polynomial is the integer n.

This is one of the first things in @jeremykun.com's "A Programmer's Introduction to Mathematics", and one of the reasons I recommend it to people. Reading a formula gives you the general gist, writing it out yourself forces you to think about each individual term.

[neon rainbow pattern background] THE EDGE OF SPACE-TIME The universe reimagined -- through pop culture, poetry, and theoretical physics. From the award-winning author of The Disordered Cosmos image of the cover of the book which features circular artwork in the center, one half of it a black and white pattern and the other half a neon rainbow pattern PREORDER NOW Coming 4/7/26 image of the Pantheon logo

📣📣 BOOK NEWS 📣📣

I'm excited to share the cover and release date of Book #2, #EdgeOfSpaceTime, which is now available for PREORDER!!

You can order from ANY bookstore, including your local indie!

More details on preordering here:
www.penguinrandomhouse.com/books/746817...

What's the book about? 🧵

Hours after ICE became the highest federal law enforcement agency in America history (and likely in world history), the Supreme Court lifts the last obstacle to ICE deporting people to any random country around the world, even in conflict zones or where migrants are enslaved.

I don’t think anyone is prepared for what they just did w/ ICE.

This is not a simple budget increase. It is an explosion - making ICE bigger than the FBI, US Bureau of Prisons, DEA,& others combined.

It is setting up to make what’s happening now look like child’s play. And people are disappearing.

Statement from DSA's National Political Committee. DSA Condemns Trump’s “Big Beautiful Bill” and Calls for House to Vote “No” July 1, 2025. 1 of 4 The Democratic Socialists of America (DSA) condemns Donald Trump’s so-called “Big Beautiful Bill”, and with its recent passage in the Senate 51-50, we urge all people of conscience to call their representatives and make their voices heard. This bill would be one of the largest cash grabs by the billionaires in world history. This bill supports massive cuts to Medicaid and will lead to as many as 17 million poor and disabled Americans losing their Medicaid and accessible healthcare cuts to rural hospitals and nursing homes will target our most vulnerable.

People will die as a result of Trump's "Big Beautiful Bill." Use this script to call the reps listed and demand they vote no: dsausa.us/stop-trumpBBB

The left better start figuring out how to weaponize today's decision rather than just (rightfully) criticizing it.

- Go back into Judge Kaczmaryk's court to dissolve all of his nationwide orders.

- Pass gun bans and insist any order applies only to plaintiffs.

later in the same paper

BREAKING: The US Supreme Court lifts limits on deporting migrants to countries not their own

YouTube video by Dev Edmonton Building an Interactive Video Player in React • May 2025 Python Ruby JS

Liqvid at Dev Edmonton! After demoing its features for teaching math and coding, I demystified how the library actually works by live-coding a stripped-down version in just a few minutes:

www.youtube.com/watch?v=UAxb...

Configuration Spaces of Points: A User's Guide This user's guide (updated version) consists of two parts. The first part is an extensive survey contributed to the Encyclopedia of Mathematical Physics, 2nd edition. It covers many of the main constr...

If you know some algebraic topology, this looks like a great introduction to configuration spaces: arxiv.org/abs/2407.11092 🧮

This stuff doesn’t look very protect-and-serve-y

🚨 Support Los Angeles immigrant communities 🚨

Please consider donating to one or all of the following orgs:

Immigrant Defenders Law Center: give.immdef.org/donate

LA Jail Support / Bail Fund:
account.venmo.com/u/jailsuppor...

Unión del Barrio:
uniondelbarrio.org/main/support...

You *must* swallow your impulse to parse and nitpick and find fault with protestors’ actions right now. We need solidarity so badly. It’s literally all we have. I am begging you, as a mother of 2 kids who is terrified of martial law, to find it in yourself to support the protestors. We need you.

Power Hungry An unprecedented look at the state of AI’s energy and resource usage, where it is now, where it is headed in the years to come, and why we have to get it right.

After months of reporting and research, I’m really excited and proud to publish this series on AI and energy. It’s a deep look at AI’s energy requirements, where that energy mix comes from, and its carbon debt.

www.technologyreview.com/supertopic/a...

As more and more homotopy theorists transition into tech, the industry will shift away from object-oriented programming languages towards complex-oriented programming languages.

Few understand this.

One of the thing that angers me most about unaccountable federal police, including ICE, but also police in general--is every step over the last 30 years to aggrandize their power has been met with warnings that exactly this would happen.

Also at the start of takes in general, I take a breath before starting speaking. It also helps to say a few things normally to avoid going into "teacher voice".

I really like this analogy