#428 – Sean Carroll: General Relativity, Quantum Mechanics, Black Holes & Aliens

**Lex Fridman** (0:00)
The following is a conversation with Sean Carroll, his third time in his podcast. He is a theoretical physicist at John Hopkins, host of the Mindscape Podcast that I personally love and highly recommend, and author of many books, including the most recent book series called The Biggest Ideas in the Universe. The first book of which is titled Space, Time, and motion, and it's on the topic of general relativity. And the second coming out on May 14th, so you should definitely pre-order it, is titled Quanta and Fields, and that one is on the topic of quantum mechanics. Sean is a legit active theoretical physicist, and at the same time, is one of the greatest communicators of physics ever. I highly encourage you to listen to his podcast, read his books, and pre-order the new book to support his work. This was, as always, a big honor and a pleasure for me.
And now, a quick few second mention of his sponsor. Check them out in the description. It's the best way to support this podcast. We got Hidden Lair for securing your AI models, Cloaked for protecting your personal information, notion for team collaboration and amazing note taking, Shopify for selling stuff on the internet, and NetSuite for business management software. Choose wisely, my friends. Also, if you want to work with our amazing team, or just get in touch with me, go to lexfreedman.com/contact. And now, on to the full ad reads. As always, no ads in the middle. I try to make this interesting, but if you skip them, please still check out our sponsors. I enjoy their stuff. Maybe you will too. This episode is brought to you by Hidden Lair, a platform that provides security for your machine learning models. Boy, is this a fascinating space. The very fabric of truth is being torn apart by increasingly powerful systems that we consult about what is true and what is not. It's really fascinating if you take all the security attacks away, how difficult it is to make sure that threats to truth-seeking mechanisms do not sort of rise above a certain threshold where we no longer know what to trust and not. I'm talking, of course, about machine-learning models that are trained on a lot of data that comes from the internet, from all the different news sources to Wikipedia, to Reddit, to all those places that they're trained on, and integrate and compress into a representation that we can then consult through natural language and ask questions about politics, about geopolitics, about wars, about history, all of that. And we turn to those models for truth, or at least to take steps towards understanding something about the world, basically engaging in a truth-seeking process. Now, if you add on top of that bad actors that want to mess with those models, so that for the most part, they appear perfectly rational and perfectly safe to use as truth-seeking mechanisms, but on certain topics, they're not. This is a real security threat as we depend on these models more and more. For general conversation, then if you're a company for very specific kind of analysis of the data that the company is focused on. So considering security of machine learning models is really, really important for companies, for people, and it's such a fascinating problem. So I'm really happy that Hidden Layer is working on this problem. And if you're a company that uses machine learning models, you should take this problem very seriously. Visit hiddenlayer.com/lex to learn more about how Hidden Layer can accelerate your AI adoption in a secure way. This episode is also brought to you by Cloaked, a platform that lets you generate a new email and phone number every time you send out for a new website. It's amazing. Like I said, it's the thing that I always hoped existed. And now that I know it exists, I'm a happier human being. So anytime you sign up to a website, this experience is taking for granted just how privacy violating it is. Because for really big websites, you kind of have this social contract, you have this trust that they're not going to steal your email and sell it to somebody else, or steal your phone number and sell it to somebody else. And that's for the most part true for large companies because they have so much to lose if they violate that social contract. But there's just a very long tail of companies, services that you sign up to, and you don't know what they're going to do with your email, your phone number, or any of the other information. So it's really nice to have Cloaked that generates a new email and phone number when you sign up. Unlimited emails and phone numbers. Every time you sign up to a thing, and it has a really nice management of those emails and phone numbers, is basically a password manager that everybody should use. Everybody should be using a password manager. And this is just a really nice password manager that has those extra privacy superpowers. So I highly recommend that you at least try it out and you play with it, because I think for the long tail of the crazy websites and services out there on the internet, this is a really good protection to keep your private info private. Go to cloaked.com/lex to get 14 days free, or for a limited time use code lexpod when signing up to get 25% off an annual cloaked plan. This episode is brought to you by notion, a note taking and team collaboration tool. It's a tool that I'm going to miss very much because in a little bit, I'm going offline for a time and no access to the internet or anything like that. No access to anything digital, really. And so the kind of notebook I'll be using is just a sheet of paper with a pen. So it's hard to express how much I've started to take for granted the incredible technology of notion for the process of note taking. And I'm talking about individual note taking. Now what they really shine at is not just the individual note taking, but the collaborative aspect between teams. And the other aspect is their AI assistant. So integrating LLMs into the process of writing note taking, summarizing all of that kind of stuff. It can help you generate a first draft. All the kind of things you know and are coming to love about LLMs, they're able to do in a really nice intuitive way. I mean, the power of LLMs is not just in the expressive capability of the raw model. It's also how you integrate that into a user interface, into a tool that you can use for solving particular tasks that you do. So for example, if you have a bunch of stuff on a team, you have a bunch of documents, like wikis and projects, the LLM knows about all of that. Their AI assistant knows about all of that, integrates all of that. You can talk to it, you can ask questions. You can generate a progress report for the stuff you've done. So I haven't used it for very large teams. I've used it for small teams, and I love it for small teams. But I almost want to work at a company that's big, that's using it, because I think it will really shine on large teams. So anyway, try notion AI for free when you go to notion.com/lex. That's all lowercase, notion.com/lex to try the power of notion AI today. This episode is also brought to you by Shopify, a platform designed for anyone to sell anywhere, with a great-looking online store. I have a store set up at lexfridman.com/store. I should probably put on more stuff there, more shirts, because shirts are fun. I love wearing shirts. Actually tweet at me or whatever if you know cool shirt places. Basically most of the time what I wear is either a suit and tie or a black shirt and jeans, but I also love owning shirts that represents something that I enjoy. For example, I have a bunch of Metallica shirts, so a bunch of shirts of the different bands I like. Lots of classic Croc, Jimi Hendrix, Led Zeppelin, Pink Floyd. I think I have a Bukowski shirt, book shirts like a Frankenstein shirt that is really cool. I have some funny shirts like Carl Jung, Forever Young, all of that kind of stuff. Anyway, if you have shirts like this, you can create a Shopify store, sell them, and spread joy into the world, but you can sell really anything, and they integrate with a bunch of third-party apps that make all of that super easy. Sign up for a $1 per month trial period at shopify.com/lex. That's all lowercase. Go to shopify.com/lex to take your business to the next level today.