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Peter LeFanu Lumsdaine's user avatar
Peter LeFanu Lumsdaine's user avatar
Peter LeFanu Lumsdaine's user avatar
Peter LeFanu Lumsdaine
  • Member for 16 years, 4 months
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About

Mathematician, math.LO/math.CT, currently Associate Professor (Universitetslektor) at Stockholm University. Mainly working in categorical logic, especially homotopy type theory and higher categories.

Previously worked at Institute for Advanced Study, Princeton; Dalhousie University, Halifax, Nova Scotia; and Carnegie Mellon University, Pittsburgh.

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Top posts

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65
Why should we believe in the axiom of regularity?
Sep 29, 2015
54
Why do people say Gödel's sentence is true when it is true in some models but false in others?
Oct 9, 2021
53
Are dagger categories truly evil?
Oct 5, 2015
53
Interesting examples of vacuous / void entities
Nov 14, 2010
50
Why are matrices ubiquitous but hypermatrices rare?
Dec 2, 2010
47
Non-examples of model structures, that fail for subtle/surprising reasons?
May 2, 2010
47
Applications of Zorn’s lemma that aren’t chain-complete/directed-complete?
Apr 18, 2021
44
Proofs where higher dimension or cardinality actually enabled much simpler proof?
May 22, 2020
41
Is a vector space naturally isomorphic to its dual?
Nov 4, 2019
40
Are there categories whose internal hom is somewhat 'exotic'?
Aug 18, 2019

Top Meta posts

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47
Why was the whole math jokes thread deleted, and should it have been?
37
Is it worth editing old posts to add links for references?
29
Why was the whole math jokes thread deleted, and should it have been?
25
Updated: Is it time to replace links to the UCDavis arXiv frontend?
23
Featured MO questions on the hot list: what benefits, if any, do these bring?

Top network posts

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408
Pedagogy: How to cure students of the "law of universal linearity"?
289
How do you explain to a 5th grader why division by zero is meaningless?
200
How do I ask for an espresso if there's a good chance they don't know how to make it?
125
Is it unethical to take a photograph of my question sheets from a sit-down exam I've just finished if I am not allowed to take them home?
113
How to deal with a professor who grades assignments and exams incorrectly