Last week I attended a wonderful Oberwolfach seminar on “Topological cyclic homology and arithmetic”. Aside from learning lots of actual math, I also learned that homotopy theorists have the best jokes. If you don’t believe me, see here or here.

# Tag: Oberwolfach

## Arithmetische geometrie

Just attended a week-long meeting at Oberwolfach on arithmetic geometry.

- “So did you do this computation like Gauss, or did you use a computer?” – Gabber to Katz

- “Let the indices work it out themselves!” – Janssen

- “Shouwu, either you’re going to answer my question, or I’m going to hand you over to Ofer!” – Kisin

- Katz (telling a story at the beginning of his talk): “… So anyway, after Spencer returned to Princeton, this is how he described the math department at Stanford [where he had just been a professor for a couple years]: ‘At Stanford, they’re still studying the topology of the unit disk!’ ”

Conrad (from the audience): “Those days are over.”

- “We use what I wrote.” – Janssen reassuring Gabber

- “So Peter, why did you turn down the breakthrough prize? [pause] I’m only asking because I’m drunk!”

- Anon.: “So Ofer, do you come here much?”

Gabber: [looks down at table, silently moves his finger across it in stepwise motion for 30 seconds] “Seventeen times.”

- Two common referees for technical papers on Shimura varieties: Frobenius and Verschiebung.

- Me (after writing down the “new” definition of a diamond): “Is that OK, Peter?”

Scholze (from the back row): “Looks good!”

- Zhang: “So Mochizuki is like the Buddha. He writes his ideas. He is satisfied. If you want to understand them, you visit him, you ask him questions, he gives you a little idea, you go away and study. You have to be a monk. Have a monk’s approach.”

Anon.: “Unfortunately, there aren’t very many good monks.”

- A “symplectic lifting whatever shit”. Apparently they’re defined in Kai-Wen Lan’s thesis?

- Gabber was NOT happy when he heard about Mochizuki’s Gaussian integral analogy.

- While eating the horrible bread casserole thing, which Kedlaya, Lieblich and I had mangled pretty badly while serving ourselves:

Lieblich:”What is this supposed to BE?”

Kedlaya: “Some kind of croque madame?”

Nizioł: “Yes, a croque madame. But I think you guys croqued it.”