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What happens if you cut a bar magnetic in half? We get two magnets, each with their own North and South poles. But what happens if you keep on cutting, into fourths and eighths and sixteenths and so on? Will we ever get to a single pole? I’ll spoil the answer for you: we don’t know! But the idea of magnetic monopoles remains one of physics’ most tantalizing maybes.
Hosted by Matt O’Dowd Written by Dan Garisto & Matt O’Dowd Graphics by Leonardo Scholzer, Yago Ballarini, Pedro Osinski, Adriano Leal & Stephanie Faria GFX Visualizations: Ajay Manuel Directed by Andrew Kornhaber Assistant Producer: Setare Gholipour Executive Producers: Eric Brown & Andrew Kornhaber.
End Credits Music by J.R.S. Schattenberg: / multidroideka.
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We know that gravity must cause clocks to run slow on the basis of logical consistency. And we know that gravity DOES cause clocks to run slow based on many brilliant experiments. But I never explained WHY or HOW gravity causes the flow of time to slow down. And I’m not going to explain it now — because in a sense it’s not true. Gravity does NOT warp the flow of time. It’s the other way around — the warping of time causes gravity.
Sign up for the mailing list to get episode notifications and hear special announcements! https://mailchi.mp/1a6eb8f2717d/space… by Matt O’Dowd Written by Matt O’Dowd Graphics by Leonardo Scholzer, Yago Ballarini, Pedro Osinski, Adriano Leal & Stephanie Faria GFX Visualizations: Katherine Kornei Directed by Andrew Kornhaber Assistant Producer: Setare Gholipour Executive Producers: Eric Brown & Andrew Kornhaber Sabine Hossenfelder’s episode “Do we travel through time at the speed of light?” • Do we travel through time at the speed of… Sound of Pulsars https://www.parkes.atnf.csiro.au/peop… End Credits Music by J.R.S. Schattenberg: / @julesschattenberg Special Thanks to Our Patreon Supporters Big Bang Sponsors Rick DeWitt Sandy Wu Matthew Miller Sean Maddox Brodie Rao Scott Gray Ahmad Jodeh Radu Negulescu Alexander Tamas Morgan Hough Juan Benet Fabrice Eap Mark Rosenthal David Nicklas Quasar Sponsor Hank S Christina Oegren Mark Heising Vinnie Falco Hypernova Sponsors william bryan Paul Stehr-Green Leo Emerson muOn Marketing Russell Pope Ben Delo L. Wayne Ausbrooks Nicholas Newlin Mark Matthew Bosko Drew Hart Jason Finn Антон Кочков Alec S-L Julian Tyacke John R. Slavik Mathew Danton Spivey Donal Botkin John Pollock Edmund Fokschaner Joseph Salomone Matthew O’Connor chuck zegar Jordan Young m0nk John Hofmann Timothy McCulloch Gamma Ray Burst Supporters Ben Campbell Lawrence Tholl, DVM Faraz Khan Almog Cohen Alex Edwards Nick Ádám Kettinger Sylvain Leduc Anthony Kahng MD3 Endre Pech Daniel Jennings Cameron Sampson Pratik Mukherjee Geoffrey Clarion Nate Adrian Posor Darren Duncan Lily kawaii Russ Creech Jeremy Reed Magistrala Хемус [Kybrit] Derek Davis Eric Webster Steven Sartore DrJYou David Johnston J. King Michael Barton Christopher Barron James Ramsey Justin Jermyn Mr T Andrew Mann Jeremiah Johnson fieldsa eleanory Peter Mertz Kevin O’Connell Richard Deighton Isaac Suttell Devon Rosenthal Oliver Flanagan Dawn M Fink Bleys Goodson Darryl J Lyle Robert Walter Bruce B Ismael Montecel Andrew Richmond Simon Oliphant Mirik Gogri David Hughes Christopher Hartnett Mark Daniel Cohen Brandon Lattin Yannick Weyns Nickolas Andrew Freeman Shane Calimlim Tybie Fitzhugh Robert Ilardi Astaurus Eric Kiebler Craig Stonaha Martin Skans Michael Conroy Graydon Goss Frederic Simon Tonyface John Robinson A G Kevin Lee Adrian Hatch Yurii Konovaliuk John Funai Cass Costello Geoffrey Short Bradley Jenkins Kyle Hofer Tim Stephani Luaan AlecZero Cody Malte Ubl King Zeckendorff Nick Virtue Scott Gossett Martin J Lollar Dan Warren Patrick Sutton John Griffith Daniel Lyons DFaulk Kevin Warne Andreas Nautsch Brandon labonte.
Does quantum mechanics allow the future to retroactively influence the past, as in the infamous delayed choice quantum eraser experiment? How about we get an actual quantum physicist–who many of you already know–to show us how to do this experiment at home, and hopefully set this matter to rest.
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If you used every particle in the observable universe to do a full quantum simulation, how big would that simulation be? At best a large molecule. That’s how insanely information dense the quantum wavefunction really is. And yet we routinely simulate systems with thousands, even millions of particles. How? By cheating. Using the ultimate compression algorithm: Density Functional Theory (DFT). Let’s learn how to cheat the universe.
Ultrafinitism, a philosophy that rejects the infinite, has long been dismissed as mathematical heresy. But it is also producing new insights in math and beyond.
Sections 0:00 — Intro 2:28 — The Problem with Deep Learning 4:17 — Intelligence is a Cake 5:15 — The Rise of Generative AI 8:00 — Blurry Images 8:54 — HRT is an awesome place to work 11:16 — But why so Blurry? 13:30 — Do our models need to be generative? 15:16 — Siamese Networks 17:53 — Representation Collapse 19:54 — Yann’s Epiphany & Barlow Twins 27:22 — DINO 28:58 — JEPA & World Models 34:09 — But is JEPA good? 36:19 — Welch Labs Book.
Special thanks to: Yann LeCun, Stephane Deny, David Fan, Nicolas Ballas.
Clip of Yann from 1989: • Convolutional Network Demo from 1989
CNN Paper: http://yann.lecun.com/exdb/publis/pdf… LeNet-5 paper: http://vision.stanford.edu/cs598_spri… Dashcam video https://commons.wikimedia.org/wiki/Fi… Image Credits https://en.wikipedia.org/wiki/File: Do… https://commons.wikimedia.org/wiki/Fi… https://commons.wikimedia.org/wiki/Fi… https://commons.wikimedia.org/wiki/Fi… https://commons.wikimedia.org/wiki/Fi… V-JEPA2 Robot Arm Videos https://ai.meta.com/research/vjepa/ PATRONS Juan Benet, Ross Hanson, Yan Babitski, AJ Englehardt, Alvin Khaled, Eduardo Barraza, Hitoshi Yamauchi, Jaewon Jung, Mrgoodlight, Shinichi Hayashi, Sid Sarasvati, Dominic Beaumont, Shannon Prater, Ubiquity Ventures, Matias Forti, Brian Henry, Tim Palade, Petar Vecutin, Nicolas baumann, Jason Singh, Robert Riley, vornska, Barry Silverman, Jake Ehrlich, Mitch Jacobs, Lauren Steely, Jeff Eastman, Rodolfo Ibarra, Clark Barrus, Rob Napier, Andrew White, Richard B Johnston, abhiteja mandava, Burt Humburg, Kevin Mitchell, Daniel Sanchez, Ferdie Wang, Tripp Hill, Richard Harbaugh Jr, Prasad Raje, Kalle Aaltonen, Midori Switch Hound, Zach Wilson, Chris Seltzer, Ven Popov, Hunter Nelson, Amit Bueno, Scott Olsen, Johan Rimez, Shehryar Saroya, Tyler Christensen, Beckett Madden-Woods, Darrell Thomas, Javier Soto, U007D, Caleb Begly, Rick Rubenstein, Brent Hunsaker, Dan Patterson, Tchsurvives, Alex Adai, Walter Reade, Zyansheep, Walter Reade, Duncan Stannett, Reginald Carey, Jean-Manuel Izaret, dh71633, Adrian Rodriguez, Dimitar Stojanovski, Michael Harder, Peter Maldonado, Emily Pesce, David Johnston, Insang Song, FaeTheWolf, Stephen Taylor, KittenKaboodle, EMatter, PATRICKMCCORMACK, John Beahan, Cameron, Cole Jones, Garrett Thornburg, Jeroen W, Rohit Sharma, GlennB, Emmanuel Cortes, Katie Quinn, Karina C, Cakra WW, Mike Ton, Eric Gometz, MacCallister Higgins, Niko Drossos, David Eraso, Tom Zehle, Steve, Brian Lineburg, rjbl, Michael Loh, Perry Vais, Bengal0, Farhad Manjoo, Sara Chipps, Ellis Driscoll, William Taysom, Will Harmon, CK, Abdullah, Peter Cho, Leo Nikora, Griffin Smith, Ash Katnoria, Alex, Markus Hays Nielsen, Catherine H., Vi, David Dobáš, Peter Wang, Sina Sohangir, Danny Thomas, Julian Francis, Hans Adler, Jiayu Peng, Weston M, Youssouf da Silva, John Thomas, Samuel Costello, Sam Adams, Bryan Liles, Malaya Zemlya, Karl, Vahe Andonians, Mike Doughty, Larry Novelo, Jonas Acres, Ludicrum Rex, Robert Blumofe, Anthony Z, Alex Zhao, Dan Babitch, Nikko Patten Supporting code: https://github.com/WelchLabs/videos Created by: Sam Baskin, Pranav Gundu, and Stephen Welch Content ID: CFAQJOTYQHT7JYIT.
April 9, 2026 This seminar covers: • How world models are increasingly moving away from reconstruction and toward prediction in latent space. • Two recent JEPA-based approaches that illustrate this shift from complementary angles.
Guest Speakers: Hazel Nam & Lucas Maes (Brown University)
Instructors: • Steven Feng, Stanford Computer Science PhD student and NSERC PGS-D scholar. • Karan P. Singh, Electrical Engineering PhD student and NSF Graduate Research Fellow in the Stanford Translational AI Lab. • Michael C. Frank, Benjamin Scott Crocker Professor of Human Biology Director, Symbolic Systems Program. • Christopher Manning, Thomas M. Siebel Professor in Machine Learning, Professor of Linguistics and of Computer Science, Co-Founder and Senior Fellow of the Stanford Institute for Human-Centered Artificial Intelligence (HAI)
