William Umboh

English is an unpossible language

Generating memes for a models of computation class

The Swiss Winter School in TCS 2026 will take place January 25-30, featuring amazing speakers Ankur Moitra (MIT), Avishay Tal (UC Berkeley), and Vera Traub (ETHZ).

Application deadline: October 24

More information: theory.epfl.ch/WinterSchool...

It feels like an insult to the notion of objective reality to invoke “experts” to weigh in on a numerical fact you can verify with a pocket calculator

e-petitions e-petitions

Official petition to the 🇦🇺 govt: make part-time PhD students' stipends tax-exempt!
www.aph.gov.au/e-petitions/...

Stipends are low but at least tax-exempt. Unless they go part time, then it becomes taxable. This disproportionately affects PhD students w/ care duties, health issues, young children..

Hi, I’d like to report a wormhole: Departing Hong Kong 0 mins ago and arriving in Melbourne in 0 minutes.

Japanese receipt made out to Weliam

Konnichiwa! My name is Weliam

Delighted to announce I have joined the board of the Association for Computational Learning (ACL) as Diversity and Inclusion Officer!

With your help, let's strive to make the learning theory conferences and community more inclusive and welcoming to all!

ACL website: learningtheory.org

Please nominate researchers for the #FOCS2025 Test of Time awards! This "recognizes papers published in past FOCS for their substantial, lasting, broad, and currently relevant impact."

Nominations due by ⏰ Sep 15. Details and guidelines: tc.computer.org/tcmf/2025/08...

Whoops sorry! Now it makes more sense :) I’m using the Dark Reader extension for Safari. I’m not sure what it’s using for the colors. I guess black? Here’s my settings in case it helps

Thank you for your amazing work! I teach finite automata, pushdown automata and Turing machines, and I would love to be able to build such lovely interactive visualizations.

Wow, this is brilliant work by @samwho.dev! It even has a built in fidget toy (of course I kept clicking on the dog for the ❤️s).

As a highly visual learner, I’m lovijg this visual introduction to big O!

Thanks to Rose Locsei for our digital sign and for helping out in the morning, Zhuo Zhang for helping out in the afternoon, and @ccanonne.github.io for suggesting to demo this algorithm!

Sign with title Algorithmagic and subtitle “Can you determine the outcome of an election using just one counter?”

A column of 4 hearts on the left and a column of 3 spades on the right

Really happy with how the algorithms display went at the University of Melbourne Open Day! We gave a demo of en.m.wikipedia.org/wiki/Boyer%E... using playing cards as votes and suits as the parties. Pairing up cards of different suits made it really clear what the algorithm is doing, IMO.

Street sign “Markov Pl”

Guess what I found on a random walk in Melbourne

YouTube video by Olivia Phillips | Math Nerd the other Hamilton’s legacy of world-changing tours… on graphs, not Broadway! #graphtheory #math

Can’t wait for part 2

youtube.com/shorts/IQp3a...

Why the Key to a Mathematical Life is Collaboration | Quanta Magazine Fan Chung, who has an Erdős number of 1, discusses the importance of connection — both human and mathematical.

If you’re at a party that has six people, Ramsey theory says there must be three people who know each other, or three people who are all strangers. But if there are only five people, this statement is not true.

A silver SUV has crashed into the side of a brick building marked "Drive-Thru Pharmacy."

i think both sides are to blame here

a little girl is riding a blue toy car with the words go go go written on it . Alt: a little girl is riding a blue toy car with the words go go go written on it .

The student and postdoc travel grant applications are open!
focs.computer.org/2025/travel-...

A photo of Darling harbour, in Sydney, with the James Craig tallship in the foreground and the skyline in the background

I'm not saying that #FOCS2025 in #Sydney will be amazing, but here's a photo I took of the city center where #FOCS2025 will be, it'll be amazing

Online algorithms: fear not which choice you make, the adversary will get you either way.

Sign in ice cream store Fluffy Torpedo in Brunswick: Fear not which choice you make, free will is an illusion

Just one more week left to apply for the International Visitor Program at SMRI! Please share this incredible opportunity with your #MathSky networks
Full T+Cs and application: mathematical-research-institute.sydney.edu.au/internationa...

A mugshot? Were you deriving under the influence again 🧐?

EVERYONE, stop everything and watch this. It’ll make your day 100x better

Seagull in the foreground with beach goers in the background making the seagull look unusually large

Accidental forced perspective at the beach

I was explaining to my Ukrainian colleague the phrase ‘There’s no such thing as a free lunch’. She told me the equivalent in Ukrainian is ‘The only free cheese is in the mousetrap’ - which is so much better

Soda drinks do not cause hangovers but #SODA2026 submissions do

Good luck to everyone that submitted!

by applying a QR decomposition, any matrix can be written as a QR code multiplied by an upper triangular matrix