Lex Fridman

Here's my conversation with Don Lincoln about some of the biggest open questions in physics, including dark energy, dark matter, the matter-antimatter imbalance, quantum vacuum, quantum foam, and the quest to unify the laws of physics. Don is a particle physicist at Fermilab who has spent decades working at the frontiers of high energy physics. He is also a great teacher & writer. I highly recommend his courses & books. One of my favorite lecture series he has given is The Evidence for Modern Physics where he breaks down the experiments that validate some of the weird laws of physics we have, and what it would take to validate even the weirder ones. It's not enough to come up with a beautiful theory. You also have to show through experiment that the theory is likely to be correct. This process often doesn't get the love it deserves, even though it's often the most important and difficult part of the scientific process. I ❤️ physics. The conversation is here on X in full and is up everywhere else (see comment). Timestamps: 0:00 - Introduction 0:49 - Unifying the laws of nature 15:20 - General relativity 32:27 - Electroweak force 44:09 - How particle colliders work 1:02:12 - Higgs boson discovery 1:12:32 - Theory of everything 1:42:17 - Physics of empty space 1:49:41 - Antimatter 2:10:31 - Dark energy 2:14:20 - Dark matter 2:42:56 - Future of physics

Here's the links for my conversation with Don Lincoln: YouTube: youtube.com/watch?v=1M3Vdl… Spotify: open.spotify.com/show/2MAi0BvDc… Podcast: lexfridman.com/podcast

Here's my conversation with Don Lincoln about some of the biggest open questions in physics, including dark energy, dark matter, the matter-antimatter imbalance, quantum vacuum, quantum foam, and the quest to unify the laws of physics. Don is a particle physicist at Fermilab who has spent decades working at the frontiers of high energy physics. He is also a great teacher & writer. I highly recommend his courses & books. One of my favorite lecture series he has given is The Evidence for Modern Physics where he breaks down the experiments that validate some of the weird laws of physics we have, and what it would take to validate even the weirder ones. It's not enough to come up with a beautiful theory. You also have to show through experiment that the theory is likely to be correct. This process often doesn't get the love it deserves, even though it's often the most important and difficult part of the scientific process. I ❤️ physics. The conversation is here on X in full and is up everywhere else (see comment). Timestamps: 0:00 - Introduction 0:49 - Unifying the laws of nature 15:20 - General relativity 32:27 - Electroweak force 44:09 - How particle colliders work 1:02:12 - Higgs boson discovery 1:12:32 - Theory of everything 1:42:17 - Physics of empty space 1:49:41 - Antimatter 2:10:31 - Dark energy 2:14:20 - Dark matter 2:42:56 - Future of physics

Coffee: form.jotform.com/230415467865159 Travel suggestions: form.jotform.com/261303042756046 General contact: lexfridman.com/contact/

I've been on a wild travel journey in China for several weeks, with only a backpack, making new friends and meeting & getting to know people from all walks of life. I've been truly humbled and inspired by everyone's kindness. Next, I'm hopping over to Taiwan (first time for me) to hang out with Jensen, attend Computex, eat a bunch of street food, and just have fun talking to all kinds of folks around the city & beyond. After that, no plans, anything goes. As always, please give travel suggestions or fill out coffee form if you want to hang out in Taiwain or anywhere else in the world. Love you all! ❤️

Form 1 - travel recommendation: form.jotform.com/261303042756046 Form 2 - coffee: form.jotform.com/230415467865159 General contact: lexfridman.com/contact/

I'm traveling the world for a bit, starting with China but then hopping around the globe, anywhere. Open to any adventure. No plans, only a backpack. Hoping to meet & get to know humans from all walks of life. The pic is from a long hike on the Great Wall. For me, as a fan of history, this was an epic experience. In China, first I'm visiting a few big cities & talking to engineers at the heart of China's AI revolution. After that, if feeling crazy enough, I'm hitchhiking (first time) across rural China for a few weeks. Hitchhiking because I think it's the best way to meet rural folks who I would otherwise never get the chance to meet. I hope to do the same in US and other places. I have a request, if you have a travel recommendation, fill out the form(s) below if you feel like it. Or share with folks who might have advice about such travel. Form 1 - travel recommendation: If you can, recommend to me an interesting place I should visit anywhere in the world. For this, fill out form 1. Not touristy stuff, but something off the beaten path, that tourists may not know about, but is legendary. It could be as remote as meeting a herder in the mountains who is a local legend. Asia, Middle East, Europe, India, South/North America, Africa, Australia, anywhere. In China, I'm hoping to visit maybe Heibei, Shanxi, Shaanxi, Gansu, Sichuan, Yunnan, etc, so recommendations for spots to visit are helpful. Form 2 - coffee: If you want to grab a coffee with me anywhere in the world, fill out form 2 (please don't use form 1 for that). Anyway, I hectically tossed stuff in backpack. Realizing I don't have a clear plan of any kind, which is probably the only way to do it. LFG. Love you all ❤️

Here's the links for my conversation all about @FFmpeg : YouTube: youtube.com/watch?v=nepKKz… Spotify: open.spotify.com/show/2MAi0BvDc… Podcast: lexfridman.com/podcast

Here's my conversation all about @FFmpeg, the legendary open-source software powering most video on the Internet. In the episode, I talk with Jean-Baptiste Kempf and Kieran Kunhya. JB is lead developer of VLC and Kieran is FFmpeg contributor, codec engineer, and the person behind the now-infamous @FFmpeg account on X. VLC (@videolan), by the way, is also a legendary piece of open-source software: it's a video player that can open basically anything & has been downloaded over 6 billion times. I think both FFmpeg and VLC are two of the most important and impactful software systems ever created, both open source, and both created & maintained by volunteers: brilliant engineers from all walks of life. Thank you to everyone who contributed to FFmpeg and VLC, and in general to all engineers giving their heart & soul to building systems used by millions (or billions) of people, and often doing so not for money, status, or fame, but purely for the love of building great software and doing good for the world. Thank you to the builders! 🙏❤️ Shoutouts in this chat to @ID_AA_Carmack @karpathy @elonmusk @TimSweeneyEpic and everyone who is a contributor & fan of open source! It's here on X in full and is up everywhere else (see comment). Timestamps: 0:00 - Episode highlight 2:17 - Introduction 5:35 - Weirdest things VLC opens 9:59 - How video playback works 19:20 - Video codecs and containers 30:07 - FFmpeg explained 51:07 - Linus Torvalds 55:46 - Turning down millions to keep VLC ad-free 1:10:04 - FFmpeg & Google drama 1:29:18 - FFmpeg developers 1:35:55 - VLC and FFmpeg 1:40:29 - History of FFmpeg 1:43:46 - Reverse engineering codecs 1:57:01 - FFmpeg testing 2:01:08 - Assembly code (handwritten) 2:25:26 - Rust programming language 2:34:42 - FFmpeg and Libav fork 2:43:04 - Open source burnout 2:50:51 - x264 and internet video 3:04:07 - Video compression basics 3:11:04 - CIA and fake VLC 3:21:39 - Ultra low latency streaming 3:39:07 - AV2 codec and video patents 3:48:59 - VLC backdoors 3:59:14 - Video archiving 4:05:51 - Future of FFmpeg and VLC

@elonmusk Agreed.

True currency is steadfast friendship

Here's the links for my conversation with historian Lars Brownworth all about the Vikings. YouTube: youtube.com/watch?v=iKx3gA… Spotify: open.spotify.com/show/2MAi0BvDc… Podcast: lexfridman.com/podcast

Here's my conversation with historian Lars Brownworth all about the Vikings, from the start of the Vikings Age to the conquest of Europe and beyond. This was an epic & mind-blowing conversation. It's here on X in full and is up everywhere else (see comment). Timestamps: 0:00 - Episode highlight 1:17 - Introduction 2:37 - The start of the Viking Age 12:30 - Viking military strategy, tactics & technology 26:13 - Ragnar Lothbrok 35:40 - The Great Heathen Army 40:23 - Rollo and Normandy 50:34 - Viking religion and Valhalla 1:01:06 - Viking explorers 1:06:13 - Vikings in North America 1:19:35 - Vikings in the East 1:39:14 - Byzantine Empire 1:47:57 - History and human nature

This life is fucking amazing. I'm so grateful to be alive, with all of you on this miracle of a planet. Oh and I'm sorry if I fuck things up sometimes. I'm a flawed human. But I promise to do whatever I can to try to add some more understanding and love to this world. After the world leader convos I get attacked intensely by all sides, and many disparate online communities. It has led to some really low points for me mentally. But I don't matter. I'm listening. I'll do better. And I'll try to find the strength to do more of them, always with rigor and backbone, seeking to truly understand. And despite accusations, I do extremely high amounts of research, sometimes 100+ hours for a conversation. Ask many of my previous guests. But when I come to the table, I put all that aside, and make it all about the other person. I don't ever try to sound smart. I know the vastness of my ignorance. But I'm trying. Sometimes I do fuck up and sound like a douche, or do something incredibly cringe. And I hate myself right after. But I'd rather fail and embarrass myself a million times, than not do what my heart says is right. And besides world leaders, historians, CEOs, engineers, etc, this year I want to travel the world and talk to a lot more everyday people on and off the mic. This is something I've wanted to do for a long time. Anyway this is written while on I'm on a 10 mile run, probably procrastinating, since to type I have to walk and not run 🤣 But I did just get stopped by a super smart and kind girl who works at a humanoid robotics company here. And she asked if she can give me a hug to thank me for being me. Sometimes the universe sends you a message that even a dumb dude like me can almost hear. I really needed that today. Thank you for the hug and the kindness 🙏 I'm just hoping she was real and I didn't just imagine that 🤣 Then again if I went full crazy might as well enjoy it! Back to the run. I love you all! ❤️

Same, I have a similar setup. A mix of Obsidian, Cursor (for md), and vibe-coded web terminals as front-end. Since I do a podcast, the number/diversity of research interests is very large. But the knowledge-base approach has been working great. For answers, I often have it generate dynamic html (with js) that allows me to sort/filter data and to tinker with visualizations interactively. Another useful thing is I have the system generate a temporary focused mini-knowledge-base for a particular topic that I then load into an LLM for voice-mode interaction on a long 7-10 mile run. So it becomes an interactive podcast while I run, where I ask it questions and listen to the answers to learn more. Anyway, heading out for a run now, thanks for the write-up 👊

LLM Knowledge Bases Something I'm finding very useful recently: using LLMs to build personal knowledge bases for various topics of research interest. In this way, a large fraction of my recent token throughput is going less into manipulating code, and more into manipulating knowledge (stored as markdown and images). The latest LLMs are quite good at it. So: Data ingest: I index source documents (articles, papers, repos, datasets, images, etc.) into a raw/ directory, then I use an LLM to incrementally "compile" a wiki, which is just a collection of .md files in a directory structure. The wiki includes summaries of all the data in raw/, backlinks, and then it categorizes data into concepts, writes articles for them, and links them all. To convert web articles into .md files I like to use the Obsidian Web Clipper extension, and then I also use a hotkey to download all the related images to local so that my LLM can easily reference them. IDE: I use Obsidian as the IDE "frontend" where I can view the raw data, the the compiled wiki, and the derived visualizations. Important to note that the LLM writes and maintains all of the data of the wiki, I rarely touch it directly. I've played with a few Obsidian plugins to render and view data in other ways (e.g. Marp for slides). Q&A: Where things get interesting is that once your wiki is big enough (e.g. mine on some recent research is ~100 articles and ~400K words), you can ask your LLM agent all kinds of complex questions against the wiki, and it will go off, research the answers, etc. I thought I had to reach for fancy RAG, but the LLM has been pretty good about auto-maintaining index files and brief summaries of all the documents and it reads all the important related data fairly easily at this ~small scale. Output: Instead of getting answers in text/terminal, I like to have it render markdown files for me, or slide shows (Marp format), or matplotlib images, all of which I then view again in Obsidian. You can imagine many other visual output formats depending on the query. Often, I end up "filing" the outputs back into the wiki to enhance it for further queries. So my own explorations and queries always "add up" in the knowledge base. Linting: I've run some LLM "health checks" over the wiki to e.g. find inconsistent data, impute missing data (with web searchers), find interesting connections for new article candidates, etc., to incrementally clean up the wiki and enhance its overall data integrity. The LLMs are quite good at suggesting further questions to ask and look into. Extra tools: I find myself developing additional tools to process the data, e.g. I vibe coded a small and naive search engine over the wiki, which I both use directly (in a web ui), but more often I want to hand it off to an LLM via CLI as a tool for larger queries. Further explorations: As the repo grows, the natural desire is to also think about synthetic data generation + finetuning to have your LLM "know" the data in its weights instead of just context windows. TLDR: raw data from a given number of sources is collected, then compiled by an LLM into a .md wiki, then operated on by various CLIs by the LLM to do Q&A and to incrementally enhance the wiki, and all of it viewable in Obsidian. You rarely ever write or edit the wiki manually, it's the domain of the LLM. I think there is room here for an incredible new product instead of a hacky collection of scripts.

Humans just launched into space, on their way to the moon (flyby around it). It'll be farthest humans have ever traveled into deep space 🤯 Congrats to all the incredible engineers & teams involved! LFG!!!!!!!

@farzyness 🤣🤣 to be continued...

@lexfridman Only 2.5 hours? I expected at least 7 hours Lex. I'm disappointed.

Here's my conversation with Jensen Huang, CEO of NVIDIA, the most valuable & one of the most influential companies in the history of human civilization. It is the engine powering the AI revolution. This was a fascinating & inspiring conversation, in parts super-technical on engineering of every part of the AI stack, memory, power, supply chain (TSMC, ASML, etc), in parts about leadership & psychology, and in parts personal & philosophical about life, consciousness, mortality, and human nature. It's here on X in full and is up everywhere else (see comment). Timestamps: 0:00 - Introduction 0:33 - Extreme co-design and rack-scale engineering 3:18 - How Jensen runs NVIDIA 22:40 - AI scaling laws 37:40 - Biggest blockers to AI scaling laws 39:23 - Supply chain 41:18 - Memory 47:24 - Power 52:43 - Elon and Colossus 56:11 - Jensen's approach to engineering and leadership 1:01:37 - China 1:09:50 - TSMC and Taiwan 1:15:04 - NVIDIA's moat 1:20:41 - AI data centers in space 1:24:30 - Will NVIDIA be worth $10 trillion? 1:34:39 - Leadership under pressure 1:48:25 - Video games 1:55:16 - AGI timeline 1:57:29 - Future of programming 2:11:01 - Consciousness 2:17:22 - Mortality

Here's the links for my conversation with Jensen Huang, CEO of NVIDIA: YouTube: youtube.com/watch?v=vif8NQ… Spotify: open.spotify.com/show/2MAi0BvDc… Podcast: lexfridman.com/podcast

It was an honor to hang out with Jensen Huang, CEO of @nvidia, and do a long-form podcast with him. Really fun & fascinating technical deep-dive conversation on & off the mic. One of the most brilliant & thoughtful human beings I've ever met. NVIDIA is the most valuable company in the world by market cap and is the engine powering the AI revolution. Podcast probably out tomorrow (Monday) unless I get stuck in too many interesting conversations while running around in SF ;-) PS: I haven't checked my messages in days. Sorry for slow replies 🙏 Trying to stay deeply focused at in overwhelmingly intense time & barely hanging on. Love you all ❤️

@kintsugiyama Awesome! I'll be there 😎

We're hosting our first public playtest next week! The Legend of California Alpha will run on Steam from March 26 - 30. Check out the links below for details and how to sign up. Sign up: bit.ly/TLOCSteam Learn more: bit.ly/TLOCAlpha