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Lex Fridman 17 Nov 2025 30 here now

David Kirtley: Nuclear Fusion, Plasma Physics, and the Future of Energy | Lex Fridman Podcast #485

David Kirtley is a nuclear fusion engineer and CEO of Helion Energy, a company working on building the world's first commercial fusion power plant by 2028.
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Many times I wake up and lex is still playing, 3 or 4 podcasts later.. Lex you ARE the BEST!
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I retired from Helion Energy in 2021. I spent 35 years working as a technician on FRC machines. About half of that at the University of Washington. 2 of Helion’s founders came from the UW. I would like to give a shout out to some of the pioneers of FRC research. These are some of the scientists I worked with over the years. Alan Hoffman. John Slough. Richard Milroy. Ed Crawford. George Vlases. Bob Brooks. Adam Pietrzyk. The other 2 founders George Votroubek and Chris Pihl. It was a privilege to work alongside these men. I’m glad I retired when I did. They were going from R&D to manufacturing. I’m a R&D guy.
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David makes me feel like I'm a PhD graduate in Nuclear Physics. So articulate and great communicator. Thanks Lex, as always skilfully holding space for your guests to unleash their world.
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I'm currently in 9th grade, and discovered a video featuring Helion while in Science class on YouTube. XD Ever since that, I've been really intrigued and interested in nuclear fusion and fission. My dad listens to your podcasts, and I just happened to overhear him playing this, which is why I am now here, listening to this podcast. I usually don't listen to podcasts, but this has piqued my interest. Thank you, Lex. : >
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Such an interesting episode! The idea of harnessing star energy for future electricity is mind-blowing. The graphics made everything so easy to understand & genuinely fun to watch. Another great show
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Исключительно интересный и вдохновляющий разговор.А очень предметная и вдумчивая проиллюстрированность его,которая действительно помогла более глубокому пониманию обсуждаемой темы, заслуживает отдельной искренней благодарности. Спасибо Вам,Лекс.
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It took me 3 days of commuting to enjoy this entire interview and I'm sad that it's over. I hope that his company and his people achieve a reset of expectations for mankind and our potential future.
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Helion’s FRC approach is probably the most innovative and effective approach to containing plasma & ultimately creation and distribution of abundance susceptible energy. David is an awesome leader…
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@ianmburke From YouTube ↗ 21 Nov 2025 10
I needed more Lex and the progress and positive movement of humanity
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Lex is so good at nailing the right questions that his Guest apreciates and smiles !
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Absolutely OUTSTANDING. Dr. Kirtley is obviously an amazing person. I've been following Helion since about 2018 and when I understood that they were trying to induce electric fields for transmission rather than steam I was like Eureka! Super exciting. I hope it works.
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@bartlx From YouTube ↗ 21 Nov 2025 87
Kirtley is one of those really great knowledgeable passionate communicators. I've been listening for one hour now and I've been glued to my screen, taking it all in like a sponge.
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Yaaaay! A conversation between two intelligent people who don't say "like" every fourth word, who don't say the same thing 3 times in a row and who don't talk over each other. Then there's the fascinating subject matter. And the graphics are cool but non-essential, so I can listen like and old-school radio broadcast. Nice work all round.
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It's mind-blowing that I can watch such valuable interviews for free
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@anluifb From YouTube ↗ 21 Nov 2025 407
I'm a physics professor. I was so bored at the start and by the end I wanted to leave academia to go work at Helion. This guy's enthusiasm is contagious.
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@mousepaddd From YouTube ↗ 21 Nov 2025 55
Editor has been doing a heavy work with those visuals. Good work.
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Please make these technical podcasts more often, not all the time because it would be really heavy to listen to but i love these once in a while.
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It's crazy this guy looks exactly like Dr.Octopus and he works with nuclear energy.
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More of these more technical interviews please. I’m not a phd. I’m a regular guy. But I can handle this. Keep it coming.
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@lexfridman From YouTube ↗ 21 Nov 2025 109
Thank you for listening ❤ Check out our sponsors: lexfridman.com/sponsors/ep485-sa
See below for timestamps, transcript, and to give feedback, submit questions, contact Lex, etc.
0:00 - Introduction
3:14 - Nuclear fission vs fusion
13:14 - Physics of E=mc^2
18:28 - Is nuclear fusion safe?
23:50 - Chernobyl
30:17 - Geopolitics
32:12 - Extreme scenarios
39:07 - How nuclear fusion works
1:11:59 - Extreme temperatures
1:17:00 - Fusion control and simulation
1:28:54 - Electricity from fusion
2:02:59 - First fusion power plant in 2028
2:09:52 - Energy needs of GPU clusters
2:20:16 - Kardashev scale
2:28:12 - Fermi Paradox

Transcript:
lexfridman.com/david-kirtley-transcript

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EPISODE LINKS:
David's X: x.com/dekirtley
David's LinkedIn: bit.ly/4qX0KXp
Helion: www.helionenergy.com/
Helion's YouTube: youtube.com/HelionEnergy

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