New handout: Intro to Proofs for the Morbidly Curious

Downloadable at https://web.evanchen.cc/handouts/NaturalProof/NaturalProof.pdf. I don't know why I thought to write this, but it's been bugging me for a year or two now that I've never seen the answer to "what is a proof" written out quite this way. So here you go. It's a bit weird for me to be writing an article that… Continue reading New handout: Intro to Proofs for the Morbidly Curious

Announcing ⛵IS, the successor to OTIS

It’s with a sense of both sadness and excitement that I am writing to announce that year IX of my math olympiad training program, OTIS, is cancelled. Instead, it will be replaced by a new program that I am starting, named Boat Operations: A Tutorial In Sailing, or ⛵IS for short. This was a hard… Continue reading Announcing ⛵IS, the successor to OTIS

Everything I need is on the ground

For me the biggest difference between undergraduate math and PhD life has been something I've never seen anyone else talk about: it's the feeling like I could no longer see the ground. To explain what this means, imagine that mathematics is this wide tower, where you start with certain axioms as a foundation, and then… Continue reading Everything I need is on the ground

Signal boost for Carina Initiatives full-time position

The Carina Initiatives (https://carina.fund) is a friend of the math education community which has supported organizations like Art of Problem Solving, BEAM, Athemath, and others. They're starting a math talent search organization in the United States and are looking to hire a full-time leader (salary $200K-$250K). Passing this along in case anyone in this space… Continue reading Signal boost for Carina Initiatives full-time position

But look at me now

Last weekend in StarCraft, the world championship at IEM Katowice 2023 saw a so-good-it-must-be-scripted Cinderella story, where Oliveira won the world championship in a totally unexpected way. It was a whole roller-coaster of upset after upset from Oliveira, and up until the grand finals we were all still asking, "this can't be, is this really… Continue reading But look at me now

Japanese EGMO is published!

I'm happy to thank 日本評論社 and their team (Fuma Hirayama, Yuki Kumagae, Taiyo Kodama, Ayato Shukuta, among others) for making the Japanese translation a reality. As well as tripling the length of the errata PDF :) This marks the second translation of the EGMO textbook (a Chinese translation was published a while ago as well… Continue reading Japanese EGMO is published!

Mystery Hunt 2023

This is a retro-post for the Mystery Hunt 2023, for which I played a somewhat minor role on the organizing team (teammate). You can play at interestingthings.museum. There is an ongoing list of write-ups about the hunt being kept at puzzles.wiki, and you may also be interested in the reddit AMA from teammate. Puzzle shoutout… Continue reading Mystery Hunt 2023

A common type-error on the OTIS application

There's a common error I keep seeing on OTIS applications, so I'm going to document the error here in the hopes that I can pre-emptively dispel it. To illustrate it more clearly, here is a problem I made up for which the bogus solution also gets the wrong numerical answer: Problem: Suppose $latex {a^2+b^2+c^2=1}&fg=000000$ for… Continue reading A common type-error on the OTIS application