Jordan Ellenberg (@JSEllenberg)

9 Jun 2021

SHAPE, my "unreasonably entertaining" new book about geometry, is a New York Times bestseller and is available now! penguinrandomhouse.com/books…

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Jordan Ellenberg · Sep 9, 2026 · 2:41 AM UTC

Sep 9

Wisconsin sports analytics and beer tomorrow night!

My colleage Sameer Deshpande, together with Shekhar Shah, and Paul Nguyen are doing Badgers on Tap Wednesday night 9/9 at 6:30pm at One Social Food Hall downtown; there will be talk about post-Mone…

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Jordan Ellenberg · Sep 8, 2026 · 5:00 AM UTC

Sep 8

Finite-time blowup

Interesting developments tonight, as Levent Alpöge and Tristan Buckmaster announce that after a fair amount of work they have constructed examples of finite-time blowup for a broad class of PDEs in…

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Jordan Ellenberg · Sep 7, 2026 · 1:55 PM UTC

Sep 7

Don’t Be Too Sure dramatis personae

I’m well underway on revising Don’t Be Too Sure, which I finished a first draft of right before surgery. A lot of people make appearances in this book, most of all William James and Joh…

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Jordan Ellenberg · Aug 28, 2026 · 1:37 PM UTC

Aug 28

New uncertainty videos!

A couple of new videos of me talking to people, which feature some themes that are going to be in Don’t Be Too Sure, as well as some stuff I’ve written about before. Both of these are l…

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Jordan Ellenberg · Aug 21, 2026 · 1:37 PM UTC

Aug 21

Brewers 22, Mariners 0

Yes, I was there! The craziest game I’ve ever seen. Seattle utility infielder Leo Rivas throwing 40mph eephus after 40mph eephus, the closest I will ever get to seeing what it would look like…

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Jordan Ellenberg · Aug 9, 2026 · 6:41 PM UTC

Aug 9

Repaired!

Hello, loyal readers! My shoulder has been repaired. All went smoothly, though the operation was substantially longer than expected, because what do you know, there were three tendons torn, not jus…

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Jordan Ellenberg · Aug 5, 2026 · 1:08 PM UTC

Aug 5

Goodbye, Adley Rutschman

At least it wasn’t the Yankees. Yes, Adley Rutchman, an Oriole yesterday, is a Red Sock today. Not much to say about it that hasn’t been said over the last 20 hours. I understand that h…

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Jordan Ellenberg · Jul 19, 2026 · 10:25 PM UTC

Jul 19

Proposed World Cup rules change

Correct outcome, but imagine if Argentina had won this on penalties without taking a single shot on goal in 120 minutes of actual play! That could easily have happened, and what an embarrassment. M…

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Jordan Ellenberg · Jul 16, 2026 · 12:51 PM UTC

Jul 16

Walking Red Flag

I have trouble sleeping — trouble staying asleep, not trouble falling asleep. I have found that the best way to get back to sleep at three or four in the morning is to listen to a podcast on …

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Jordan Ellenberg · Jul 4, 2026 · 1:49 PM UTC

Jul 4

American Revolution

I was in Philadelphia a couple of weeks ago with AB and we went to the brand-new Museum of the American Revolution. It’s a great work of public history. Every American, and everybody else w…

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Jordan Ellenberg · Jun 17, 2026 · 1:08 PM UTC

Jun 17

More shoulderblogging

It is possible to open a a peanut butter jar one-handed; the trick is to grasp the jar between the knees and then twist with the left hand. However, I have not figured out how to get a knifeload of…

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Jordan Ellenberg · Jun 15, 2026 · 1:55 PM UTC

Jun 15

People are good and the system works

Yesterday I hit a pothole while biking up N. Allen St. and flew over my handlebars. Lying on the street, unable to get up, bleeding all over the asphalt. Several people stopped to help; one neighbo…

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Jordan Ellenberg · Jun 8, 2026 · 1:55 PM UTC

Jun 8

Recent progress around Cohen-Lenstra heuristics (notes from a Bourbaki talk)

These are the notes from the recent Bourbaki seminar I gave about just some of the remarkable work people have done around the Cohen-Lenstra conjectures in the past few years. I have to submit the …

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Jordan Ellenberg · Jun 5, 2026 · 1:37 PM UTC

Jun 5

Human character, continuity of

“Let’s hazard an assertion: On or about June 2007, human character changed. To be more exact—because the phrase human character now feels antique—we might say instead that the human sensorium…

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Jordan Ellenberg · Jun 4, 2026 · 11:22 PM UTC

Jun 4

The Leiden Declaration on Artificial Intelligence and Mathematics

A well-thought-out statement. One thing I like about it is that it is not in any way anti-AI; the declaration merely says that, as with any other piece of technology, we should use it in ways that …

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Jordan Ellenberg · May 25, 2026 · 4:40 PM UTC

May 25

Memorial Day

Tomorrow is Memorial Day. William James, in 1897, dedicating the monument to Col. Robert Gould Shaw and the 54th regiment, a monument which still stands in Boston Common today: “And when Sout…

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Jordan Ellenberg · May 19, 2026 · 2:51 PM UTC

May 19

Roger Brown on “Ms.”

In the fall of 1992, my senior year of college, I took a seminar on Social Psychology of Language with Roger Brown. (Roger Brown the psychologist, not Roger Brown the painter, one of my very favori…

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Jordan Ellenberg · Apr 9, 2026 · 1:49 PM UTC

Apr 9

Minor Epiphany Concerning the World Columbian Exposition of 1894 and John Hughes

It was felt that the 1894 exposition in Chicago needed a big iron monument to rival the Eiffel Tower, and a man named George Washington Gale Ferris had the decisive insight that what the occasion d…

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Jordan Ellenberg · Apr 8, 2026 · 1:08 PM UTC

Apr 8

Brewers 8, Red Sox 6

I was in Boston for Pesach and stuck around an extra day because some more Wisconsinites, the mighty Milwaukee Brewers, were also coming into town to play the Boston nine. CJ and I took in the game…

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Jordan Ellenberg · Apr 7, 2026 · 1:04 PM UTC

Apr 7

Armiversary

Twenty years ago this week (I thought it was twenty years ago today, but I just went back and checked and it was April 3, 2006) I fell down a flight of stairs at MSRI and broke the absolute fuck ou…