Emily Riehl Makes Infinity Categories Elementary

Emily Riehl, one of the world’s leading category theorists, shares her vision for making infinity category theory something undergrads can actually learn. In this talk, she breaks down how rethinking the foundations of math could change the way it’s taught and understood—and why it might redefine what math even is. I personally subscribe to The Economist. SUMMER SALE to Aug 17, 2026: 50% off the annual subscription! No other podcast has this! https://economist.com/TOE Join My New Substack (Personal Writings): https://curtjaimungal.substack.com Listen on Spotify: https://tinyurl.com/SpotifyTOE Become a YouTube Member (Early Access Videos): https://www.youtube.com/channel/UCdWIQh9DGG6uhJk8eyIFl1w/join Links: •⁠ ⁠Emily’s profile: https://emilyriehl.github.io/ •⁠ ⁠Emily’s presentation: https://emilyriehl.github.io/files/undergraduates-TOE.pdf •⁠ ⁠A Type Theory For Synthetic ∞-Categories (paper): https://arxiv.org/pdf/1705.07442 •⁠ ⁠Could ∞-Category Theory Be Taught To Undergraduates? (paper): https://arxiv.org/pdf/2302.07855 •⁠ ⁠RZK proof assistant: https://rzk-lang.github.io/rzk/en/latest/ •⁠ ⁠Lean Zulip chat: https://leanprover.zulipchat.com/#recentnews Timestamps: 00:00 A Dream for the Future 01:55 Exploring Infinity Categories 03:54 The Role of Category Theory 10:17 Key Concepts of Category Theory 12:01 The Curry-Howard Correspondence 15:37 Understanding Left Adjoint Functors 24:38 The Innate Lemma Explained 38:29 Proving the Isomorphism 41:50 The Importance of Abstraction 44:04 A Crash Course in Category Theory 44:17 Introduction to Infinity Category Theory 56:27 Fundamental Infinity Groupoids 1:03:34 What Are Infinity Categories? 1:09:12 The Case for Infinity Categories 1:18:12 Transitioning to Homotopy Type Theory 1:22:49 Crash Course in Homotopy Type Theory 1:30:56 Type Constructors Explained 1:34:19 Propositions as Types 1:42:50 Understanding Dependent Types 1:49:01 Identity Types and Their Importance 1:54:03 The Structure of Infinity Groupoids 1:59:33 Hierarchies of Types 2:06:19 The Univalence Axiom 2:08:36 Transitioning to Infinity Category Theory 2:10:04 Simplicial Type Theory Overview 2:14:56 Pre-Infinity Categories Defined 2:24:32 Isomorphisms in Infinity Categories 2:31:48 Computer Formalization in Mathematics 2:40:02 Conclusion and Future Directions Support TOE on Patreon: https://patreon.com/curtjaimungal Crypto: https://nowpayments.io/donation/TOE Twitter: https://twitter.com/TOEwithCurt Discord Invite: https://discord.com/invite/kBcnfNVwqs #science Learn more about your ad choices. Visit megaphone.fm/adchoices