Can you really swing from spider silk? Sponsored by Henson Shaving - Head to https://hensonshaving.com/veritasium and use code “veritasium” for 100 free blades with any razor purchase. Just add both the razor and blades to your cart. Last year, we launched the Elements of Truth game on Kickstarter and were thrilled by the response. We’re now in the final stages of production, with Kickstarter rewards shipping soon. Pre-order the retail edition here: https://ve42.co/YTSpiderSilk If you’re looking for a molecular modelling kit, try Snatoms, a kit I invented where the atoms snap together magnetically - https://ve42.co/SnatomsV For weekly science news, sign up to the Veritasium newsletter - https://ve42.co/Newsletter For early access to work-in-progress videos, join our Patreon - https://ve42.co/VePatreon ▀▀▀ 00:00 Could Spider Silk Let You Swing Like Spider-Man? 00:44 Is Spider Silk Really Stronger Than Steel? 02:29 Testing Spider Silk's Tensile Strength 03:48 The Strongest Silk on Earth 05:34 Spider Silk vs Kevlar vs Steel 07:37 The Nanostructure Behind Spider Silk's Strength 08:42 Why We Can't Farm Spiders 10:16 Engineering Fake Spider Silk 15:04 From the Silk Road to CRISPR 21:31 Real-World Uses and the Ultimate Swing Test ▀▀▀ Special thanks to the experts and collaborators who made this video possible: Professor Todd Blackledge and the Blackledge Spider Lab at the University of Akron, for welcoming us into the lab, walking us through how spiders make and use silk, and letting us put the real material to the test. Jon Rice and the team at Kraig Biocraft Laboratories, for opening their doors, sharing their transgenic silk, patiently explaining how their engineered silkworms work, and helping make the spider-silk swing possible. Professors Keiji Numata, Chris Holland, Sara Goodacre and Greg Holland, for generously sharing their time and expertise in our research conversations helping us understand the extraordinary diversity of spider silks, how they are spun, and how structure, water and chemistry shape their properties. Professors Ingi Agnarsson and Thomas Scheibel, for their guidance that helped sharpen our explanation. ▀▀▀ References: https://ve42.co/SpiderSilkRefs ▀▀▀ Special thanks to our Patreon supporters: Adam Foreman, Albert Wenger, Alex Porter, Alexander Tamas, André Powell, Anton Ragin, Balkrishna Heroor, Bertrand Serlet, Blake Byers, Bruce, Bryan Ackermann, Chris Brewer, Data Don, Dave Kircher, David Johnston, David Tseng, EJ Alexandra, Evgeny Skvortsov, Garrett Mueller, Gnare, gpoly, Hayden Christensen, Hong Thai Le, Ibby Hadeed, Jeromy Johnson, Jesse Brandsoy, Juan Benet, Kelcey Steele, KeyWestr, Kyi, Lee Redden, Marinus Kuivenhoven, Mark Heising, Martin Paull, Meekay, meg noah, Michael Krugman, Moebiusol - Cristian, Orlando Bassotto, Parsee Health, Paul Peijzel, Robson, Sam Lutfi, Shalva Bukia, Sinan Taifour, Sweet_Nemo, Tj Steyn, Ubiquity Ventures, Vahe Andonians, wolfee ▀▀▀ Writers - Vibhor Pandey & Henry van Dyck Producer & Director - Vibhor Pandey & Henry van Dyck Presenters & Narration - Henry van Dyck & Derek Muller Editors- Trenton Oliver, Axel Oliver, James Stuart & George Reynolds Animators - Alex Drakoulis, Andrew Neet, Domonkos Józsa, Emma Wright & Fabio Albertelli Illustrator - Jakub Misiek Researchers - Aakash Singh Bagga, Gabe Strong & Sophia Rose Camera Operators: Henry van Dyck, Petr Lebedev, Casper Mebius and Ben Curtis-Dyck Thumbnail Designers - Abdallah Rabah, Daniel Ellacott & Ben Powell Production Team - Matthew Cavanagh, Jess Bishop-Laggett, Glen Griffiths, Josh Pitt, Luke Lewis, Anna Milkovic & Justin St-Laurent Executive Producers - Henry van Dyck, Emilia Gyles, Casper Mebius & Derek Muller Additional video/photos supplied by Getty Images, Pond5 and Storyblocks Music from Epidemic Sound

How do you measure big forces accurately? By calibrating your force transducer on the world's biggest weight - 1,000,000 pounds of force. This machine ensures planes don't break apart, jets provide required thrust, and rockets make it to their destination.

The hidden math that governs life. Sponsored by Brilliant - Try Brilliant for free, plus get 20% off an annual Premium subscription at https://brilliant.org/veritasium Last year, we launched the Elements of Truth game on Kickstarter and were thrilled by the response. We’re now in the final stages of production, with Kickstarter rewards shipping soon. Pre-order the retail edition here: https://elementsoftruth.game/ If you’re looking for a molecular modelling kit, try Snatoms, a kit I invented where the atoms snap together magnetically - https://ve42.co/SnatomsV For weekly science news, and an exclusive Q&A where Writer/Director Daniel Leonard discusses the making of this video, sign up to the Veritasium newsletter - https://ve42.co/Newsletter For early access to work in progress videos join our Patreon - https://ve42.co/VePatreon ▀▀▀ 0:00 How much LSD should you give an elephant? 3:09 Metabolic Rate In Animals 5:27 The Surface Law 8:04 What is Kleiber’s Law? 10:49 Why is ¼ everywhere in biology? 13:33 WBE Theory 19:53 Every animal has 1,000,000,000 heartbeats 23:11 Why Humans Live Longer 24:31 Is it better to live in a city or a small town? 30:12 Is there really a universal scaling exponent for life? ▀▀▀ Much of this video was inspired by Geoffrey West’s book: Scale. Check it out here - https://ve42.co/ScaleBook ▀▀▀ Special thanks to the experts who helped make this video possible: Brian Enquist, whose work helped inspire this video, for sharing the story behind WBE theory and helping us make its key assumptions and derivation more accurate. Van Savage, for the generous and detailed feedback that sharpened our explanation of WBE theory, self-similarity, and the current state of the field. Steven Strogatz, for the insightful conversations, on-camera contribution, and careful reviews that helped us keep the mathematics clear and the story scientifically honest. Peter Sheridan Dodds, for helping us understand the objections to WBE theory and the debate over three-quarter-power scaling. And the many other experts who discussed this topic with us as we were developing the script, for their invaluable contributions: Luis Bettencourt, Jayanth Banavar, Aaron Clauset, Juan Rubalcaba, and Douglas Glazier. ▀▀▀ References: https://ve42.co/ScaleRefs ▀▀▀ Special thanks to our Patreon supporters: Adam Foreman, Albert Wenger, Alex Porter, Alexander Tamas, André Powell, Anton Ragin, Balkrishna Heroor, Bertrand Serlet, Blake Byers, Bruce, Bryan Ackermann, Chris Brewer, Data Don, Dave Kircher, David Johnston, David Tseng, EJ Alexandra, Evgeny Skvortsov, Garrett Mueller, Gnare, gpoly, Hayden Christensen, Hong Thai Le, Ibby Hadeed, Jeromy Johnson, Jesse Brandsoy, Juan Benet, Kelcey Steele, KeyWestr, Kyi, Lee Redden, Marinus Kuivenhoven, Mark Heising, Martin Paull, Meekay, meg noah, Michael Krugman, Moebiusol - Cristian, Orlando Bassotto, Parsee Health, Paul Peijzel, Robson, Sam Lutfi, Shalva Bukia, Sinan Taifour, Sweet_Nemo, Tj Steyn, Ubiquity Ventures, Vahe Andonians, wolfee ▀▀▀ Writers - Daniel Leonard, Casper Mebius & Derek Muller Producer & Director - Daniel Leonard Presenters & Narration - Derek Muller & Henry van Dyck Editors - Trenton Oliver, Axel Oliver & Jonny Lennard Assistant Editor - James Stuart Animators - Alex Drakoulis, Andrew Neet, Domonkos Józsa, Emma Wright & Fabio Albertelli Illustrators - Jakub Misiek & Raphael Aubry Camera Operator - Chris Anstis Simulations - Callum Cuttle & Aakash Singh Bagga Researchers - Aakash Singh Bagga, Callum Cuttle & Gabe Strong Thumbnail Designers - Abdallah Rabah & Daniel Ellacott Thumbnail Design Direction - Ben Powell Production Team - Jess Bishop-Laggett, Glen Griffiths, Matthew Cavanagh, Luke Lewis, Anna Milkovic & Justin St-Laurent Executive Producers - Casper Mebius & Derek Muller Additional video/photos supplied by Getty Images, Pond5 and Storyblocks Music from Epidemic Sound

Put a cat in a box with a radioactive atom. Add a radiation detector that triggers the release of poisonous cyanide gas. Schrödinger's thought experiment was supposed to be a criticism of quantum mechanics and is now one of it's best explainers. Here's why and what happens to the cat...

Why do objects travel with waves? We're taught waves only transfer energy, not material, but objects wash ashore all the time. How does this work? #veritasium #science #physics

Why is the Smith Chart one of the scariest charts in electrical engineering? Sponsored by Incogni - use code veritasium at https://incogni.com/veritasium to get an exclusive 60% off your annual subscription. Last year, we launched the Elements of Truth game on Kickstarter and were thrilled by the response. We’re now in the final stages of production, with Kickstarter rewards shipping soon. Pre-order the retail edition here: https://elementsoftruth.game/ If you’re looking for a molecular modelling kit, try Snatoms, a kit I invented where the atoms snap together magnetically - https://ve42.co/SnatomsV For weekly science news, and an exclusive Q&A where Writer/Director Henry discusses the making of this video, sign up to the Veritasium newsletter - https://ve42.co/Newsletter For early access to work in progress videos join our Patreon https://ve42.co/VePatreon ▀▀▀ 0:00 The Scariest Chart In Engineering 3:24 Standing Waves And Reflections 7:24 Why does a wave bounce back? 10:15 How to stop a wave from bouncing back 17:06 The Smith Chart 25:53 How To Read The Smith Chart 30:42 This Circuit Gets Better When You Break It 35:22 Why were we slow to use it? 37:06 Is it still useful? ▀▀▀ A big shout out to Imperial College London for letting us use their screened RF anechoic chamber. In particular, a massive thanks to Prof. Stepan Lucyszyn and Ian Rossuck for helping us set up the demos seen in this video. Also special thanks to Zach Star, Dr. Cynthia Furse, Dr James Nagel, and Ralph Gable for their invaluable expertise! Check out @zachstar 's video on the Smith Chart here: https://www.youtube.com/watch?v=pXWbdxOAuDs Check out @3blue1brown 's video to learn more about transformations and conformal maps: https://www.youtube.com/watch?v=ldxFjLJ3rVY ▀▀▀ References: https://ve42.co/SmithChartsRefs ▀▀▀ Special thanks to our Patreon supporters: Adam Foreman, Albert Wenger, Alex Porter, Alexander Tamas, André Powell, Anton Ragin, Balkrishna Heroor, Bertrand Serlet, Blake Byers, Bruce, Bryan Ackermann, Chris Brewer, Data Don, Dave Kircher, David Johnston, David Tseng, EJ Alexandra, Evgeny Skvortsov, Garrett Mueller, Gnare, gpoly, Hayden Christensen, Hong Thai Le, Ibby Hadeed, Jeromy Johnson, Jesse Brandsoy, Juan Benet, Kelcey Steele, KeyWestr, Kyi, Lee Redden, Marinus Kuivenhoven, Mark Heising, Martin Paull, Meekay, meg noah, Michael Krugman, Moebiusol - Cristian, Orlando Bassotto, Parsee Health, Paul Peijzel, Richard Sundvall, Robson, Sam Lutfi, Shalva Bukia, Sinan Taifour, Tj Steyn, Ubiquity Ventures, Vahe Andonians, wolfee ▀▀▀ Writer, Producer & Director: Henry van Dyck Presenter: Henry van Dyck Editors: Trenton Oliver, Axel Oliver & Peter Nelson Animators: Emma Wright, Alex Drakoulis, Andrew Neet & Fabio Albertelli Illustrator: Jakub Misiek Researchers: Darius Garewal & Gabe Strong Asst. Editors: James Stuart & Jonny Leonard Simulations: Darius Garewal & Henry van Dyck Camera/Drone Operators: Robert Newman & Xavier Bussière Additional Writing: Darius Garewal Thumbnail Designers: Abdallah Rabah & Daniel Ellacott Production Team: Jess Bishop-Laggett, Glen Griffiths, Matthew Cavanagh, Luke Lewis & Anna Milkovic Executive Producers: Casper Mebius Additional video/photos supplied by Getty Images and Storyblocks Music from Epidemic Sound

The blender problem. Do you think you know the answer? Comment below!

Light is the fastest thing in the universe. In order to be this fast it always needs to take the shortest path (as it's speed cannot change). So how does it always know what the shortest path is?

Plants can stay cooler than the air around them, even in full sun. How is that possible? We partnered with Anker to find out… Pick up your Anker Prime Charger here: https://ankerfast.club/noagy5 #AnkerTech #Anker #AnkerPrime

Why does a charger sometimes spark when you unplug it, even when it's switched off at the wall? We partnered with Anker to find out… Pick up your Anker Prime Charger here: https://ankerfast.club/noagy5 #AnkerTech #Anker #AnkerPrime

Watch what happens when you start a metronome ticking on an unstable platform, out of sync with two others. Slowly over time, they all sync up. How does this happen?

How accurate is modern forensics? Sponsored by Saily - Get an exclusive 15% discount on Saily data plans! Use code veritasium at checkout. Download the Saily app or go to https://saily.com/veritasium Last year, we launched the Elements of Truth game on Kickstarter and were thrilled by the response. We’re now in the final stages of production, with Kickstarter rewards shipping soon. If you missed the campaign, you can now pre-order the retail edition through our new website here - https://ve42.co/ForensicsDes If you backed us on Kickstarter, don’t worry, your game will ship before any pre-orders are fulfilled. If you’re looking for a molecular modelling kit, try Snatoms, a kit I invented where the atoms snap together magnetically - https://ve42.co/SnatomsV For the latest science news, and for an exclusive bonus Q&A with the director of this video, sign up to the Veritasium newsletter - https://ve42.co/Newsletter For early access to work-in-progress videos, join our Patreon https://ve42.co/VePatreon Correction: At 2:47, we state 96% of cases were declared false, the FBI report found that examiners gave erroneous or exaggerated testimony under oath in 96% of those cases. ▀▀▀ 0:00 The First Forensics Investigation 1:51 How accurate is hair in forensics? 3:30 Why Bite Marks Should Never Be Used In Court 5:22 Blood Spatter Analysis 8:04 How unique are fingerprints? 16:33 Is DNA evidence reliable? 21:38 How can we improve forensics as a science? ▀▀▀ Special thanks to the experts and collaborators who made this video possible: For their fantastic insights and time in contributing to this video (in order of appearance) - Dr Mary Bush from the University at Buffalo, John Foster at the University of Greenwich, Dr Itiel Dror, and Professor Turi King. For key expertise and consultation on the animations as well as wider research, Professor Denise Syndercombe Court of King’s College London and Dr John Butler of the National Institute for Standards and Technology. For their expert contributions to the development and research of the video (in alphabetical order), Zack Kowalske (@TheScienceDetective), Dr Emmanuel Nsiah Amoako, Professor Nick Scurich, Derek Tremain, Dr Sophie Turfus, Theron Vines, Professor Graham Williams and Jerri Williams. For key inspiration in the making of this video, Forensics: The Anatomy of Crime by Val McDermid, Patented: History of Inventions Podcast by History Hit, Murder Is Her Hobby: Frances Glessner Lee and The Nutshell Studies of Unexplained Death Exhibition at the Smithsonian American Art Museum, deathindiorama.com, and @forensicsprof videos on the Henry Classification System for fingerprint analysis. ▀▀▀ Reference List: https://ve42.co/ForensicsRefs ▀▀▀ Special thanks to our Patreon supporters: Adam Foreman, Albert Wenger, Alex Porter, Alexander Tamas, André Powell, Anton Ragin, Balkrishna Heroor, Bertrand Serlet, Blake Byers, Bruce, Bryan Ackermann, Chris Brewer, Data Don, Dave Kircher, David Johnston, David Tseng, EJ Alexandra, Evgeny Skvortsov, Garrett Mueller, Gnare, gpoly, Hayden Christensen, Hong Thai Le, Ibby Hadeed, Jeromy Johnson, Jesse Brandsoy, Juan Benet, Kelcey Steele, KeyWestr, Kyi, Lee Redden, Marinus Kuivenhoven, Mark Heising, Martin Paull, Meekay, meg noah, Michael Krugman, Moebiusol - Cristian, Orlando Bassotto, Parsee Health, Paul Peijzel, Richard Sundvall, Robson, Sam Lutfi, Shalva Bukia, Sinan Taifour, Tj Steyn, Ubiquity Ventures, Vahe Andonians, wolfee ▀▀▀ Writers: Sarah Houlton and Gregor Čavlović Producer and Director: Sarah Houlton Presenter: Gregor Čavlović Editors: Trenton Oliver and Axel Oliver Assistant Editors: James Stuart and Peter Nelson Animators: Emma Wright, Domonkos Józsa, Alex Drakoulis, Andrew Neet and Fabio Albertelli Illustrator: Jakub Misiek Researchers: Sophia Rose and Gabe Strong Director of Photography: Richard Ing Camera Assistant: Jack Stevenson Additional Camera: Sarah Houlton Additional Writer: Sophia Rose Thumbnail Designers: Abdallah Rabah, Daniel Ellacott, Patryk Ziolkowski and Ben Powell Production Team: Jess Bishop-Laggett, Glen Griffiths, Matthew Cavanagh, Anna Milkovic and Justin St Laurent Executive Producers: Gregor Čavlović and Casper Mebius Additional video/photos supplied by Getty Images and Storyblocks Music from Epidemic Sound

Scientists have developed a new way to provide treatment for brain tumours. Currently we use chemotherapy, but that's like throwing a grenade at a mosquito, you end up damaging a lot more than you mean to. This magnetic blob will help change that. References: Microrobots: https://www.science.org/stoken/author-tokens/ST-3054/full https://www.nature.com/articles/d41586-025-03754-6 https://www.washingtonpost.com/science/2025/11/19/robot-drugs-side-effects-magnets/ Catheters: https://www.science.org/doi/full/10.1126/scirobotics.adh0298 Telesurgery: https://www.science.org/doi/10.1126/scirobotics.ado3187 https://www.science.org/doi/full/10.1126/scirobotics.adq0192 Electromagnetic Navigation Systems: https://advanced.onlinelibrary.wiley.com/doi/10.1002/adma.202310701 Magnetic Levitation: https://www.youtube.com/watch?v=WT8129liuQc

Do twin primes go on forever? Sponsored by Brilliant - Head to https://brilliant.org/veritasium to try Brilliant’s tutor for free, plus receive 20% off an annual Premium subscription If you’re looking for a molecular modelling kit, try Snatoms, a kit I invented where the atoms snap together magnetically - https://ve42.co/SnatomsV Sign up for the Veritasium newsletter for weekly science updates - https://ve42.co/Newsletter For early access to work in progress videos join our patreon https://ve42.co/VePatreon ▀▀▀ A huge thank you to Alex Kontorovich, Andrew Granville, James Maynard, Roger Heath-Brown, Dimitris Koukoulopoulos, Debmalya Basak & George Shakan for their invaluable expertise and contributions to this video! ▀▀▀ 0:00 What are twin primes? 3:08 How To Find Prime Numbers 6:11 The Sieve of Eratosthenes 11:26 The Closest We’ve Come To Proving Twin Primes 15:54 Searching For A Bounded Gap 18:47 How A Subway Worker Changed The Game 29:20 Finding An Upper Bound 32:04 Maynard and Polymath 36:42 Will we solve the twin prime conjecture? ▀▀▀ References can be found here: https://ve42.co/TwinPrimesRefs ▀▀▀ Special thanks to our Patreon supporters: Adam Foreman, Albert Wenger, Alex Porter, Alexander Tamas, Anton Ragin, armedtoe, Balkrishna Heroor, Bertrand Serlet, Blake Byers, Bruce, Charles Ian Norman Venn, Daniel Martins, Data Don, Dave Kircher, David Johnston, David Tseng, EJ Alexandra, Evgeny Skvortsov, Garrett Mueller, Gnare, Hayden Christensen, Hong Thai Le, Ibby Hadeed, Jeromy Johnson, Jesse Brandsoy, Jon Jamison, Juan Benet, Kelcey Steele, KeyWestr, Kyi, Lee Redden, Marinus Kuivenhoven, Mark Heising, Martin Paull, Meekay, meg noah, Michael Krugman, Moebiusol - Cristian, Orlando Bassotto, Parsee Health, Paul Peijzel, Richard Sundvall, Robson, Sam Lutfi, Shalva Bukia, Sinan Taifour, Tj Steyn, Ubiquity Ventures, Vahe Andonians, wolfee ▀▀▀ Writers: Vibhor Pandey, Casper Mebius and Alex Kontorovich Producer & Director: Vibhor Pandey Presenters: Derek Muller & Casper Mebius Editors: George Reynolds & Trenton Oliver Camera Operators: Casper Mebius & Derek Muller Animators: Emma Wright, Andrew Neet, Alex Drakoulis, Domonkos Józsa & Fabio Albertelli Illustrators: Jakub Misiek Additional Editor: James Stuart Researchers: Darius Garewal, Gabe Strong, Sophia Rose Thumbnail Designers: Abdallah Rabah, Ben Powell, Daniel Ellacott & Patryk Ziolkowski Production Team: Jess Bishop-Laggett, Matthew Cavanagh, Anna Milkovich & Josh Pitt Executive Producers: Derek Muller, Casper Mebius & Emily Zhang Additional video/photos supplied by Getty Images & Storyblocks Music from Epidemic Sound

How do zippers work? We made a giant one to find out!

The balls in a Galton board fall down randomly. Any time they come to a junction they can take any number of paths and it's almost impossible to accurately predict every ball's trajectory. However, the system as a whole is predictable. How can this be? How can random systems actually be predictable?

How does a traffic light know when a car is there? Pick up your Anker Prime Charger here: https://ankerfast.club/noagy5 #AnkerTech #Anker #AnkerPrime

Something is disrupting GPS signals across Europe. Sponsored by Ground News. Go to https://ground.news/Ve for 40% off the unlimited Vantage plan. In 2025, we launched the Elements of Truth game on Kickstarter and were thrilled by the response. We’re now in the final stages of production, with Kickstarter rewards shipping soon. If you missed the campaign, you can now pre-order the retail edition through our new website here - https://ve42.co/GPSJam If you’re looking for a molecular modelling kit, try Snatoms, a kit I invented where the atoms snap together magnetically - https://ve42.co/SnatomsV Sign up for the Veritasium newsletter for weekly science updates - https://ve42.co/Newsletter ▀▀▀ 0:00 What is jamming Europe’s GPS? 4:43 How does GPS work? 10:46 How easy is it to jam GPS? 12:18 The Hunt To Find The Jammer 17:12 Who are the possible culprits? 20:06 The Investigation Goes Public 23:00 Narrowing In On The Jammer 25:15 Cosmos 2546 28:25 A Secret Messaging Service? 29:19 What happens if we lose GPS? ▀▀▀ Special thanks to the experts and collaborators who made this video possible: Professor Todd Humphreys and Dr Zach Clements at the University of Texas at Austin, whose research this story is based on - thank you for sharing your data, your time, and the inside story of the hunt. Ramsey Faragher, Director of the Royal Institute of Navigation, for the brilliant interview, feedback and stories that helped to shape this video. Richard D. Easton, for helping us understand the history of GPS. Dana Goward, President of the Resilient Navigation and Timing Foundation, for providing context on interference and alternative systems. Richard Bowden and Luis Enrique Aguado from GMV for sharing their independent work tracing the source of the interference. Ben Watts, for sharing his first-hand experience of GPS jamming and spoofing from the cockpit. KeepTrack (https://keeptrack.space/) for generously giving us access to their satellite-tracking software, which we used to visualise the search through 15,000 satellites for the culprit. And to GPSWise (https://gpswise.aero/) for kindly providing their software which we used to visualise GPS jamming and spoofing. Bartosz Ciechanowski, whose interactive GPS explainer (https://ciechanow.ski/gps/) was a great resource for research and the basis for one of our technical animations. Thank you for allowing us to build on your work. ▀▀▀ References: Clements, Z. L., Kriezis, A., & Humphreys, T. E. (2026). Chasing Lightning: Detecting, Characterizing, and Identifying a Powerful Space-Based GNSS Interference - https://ve42.co/GNSSInterference The rest here: https://ve42.co/GPSJammingRefs ▀▀▀ Special thanks to our Patreon supporters: Adam Foreman, Albert Wenger, Alex Porter, Alexander Tamas, André Powell, Anton Ragin, Balkrishna Heroor, Bertrand Serlet, Blake Byers, Bruce, Bryan Ackermann, Chris Brewer, Data Don, Dave Kircher, David Johnston, David Tseng, EJ Alexandra, Evgeny Skvortsov, Garrett Mueller, Gnare, gpoly, Hayden Christensen, Hong Thai Le, Ibby Hadeed, Jeromy Johnson, Jesse Brandsoy, Juan Benet, Kelcey Steele, KeyWestr, Kyi, Lee Redden, Marinus Kuivenhoven, Mark Heising, Martin Paull, Meekay, meg noah, Michael Krugman, Moebiusol - Cristian, Orlando Bassotto, Parsee Health, Paul Peijzel, Richard Sundvall, Robson, Sam Lutfi, Shalva Bukia, Sinan Taifour, Tj Steyn, Ubiquity Ventures, Vahe Andonians, wolfee ▀▀▀ Writer, Producer & Director: Emilia Gyles Presenters: Derek Muller & Gregor Čavlović Editor: Peter Nelson Asst. Editor & Sound Designer: James Stuart Animators: Domonkos Józsa, Emma Wright, Alex Drakoulis & Andrew Neet Illustrators: Jakub Misiek & Maria Gusakovich Stop Motion: Sulli Yost Researchers: Aakash Singh Bagga, Sophia Rose & Callum Cuttle Thumbnail Designers: Abdallah Rabah, Ren Hurley, Ben Powell & Daniel Ellacott Production Team: Jess Bishop-Laggett, Matthew Cavanagh & Anna Milkovic Executive Producers: Casper Mebius, Derek Muller & Gregor Čavlović Additional video/photos supplied by Getty Images and Storyblocks Music from Epidemic Sound

The math behind Google Maps. Sponsored by boot.dev - Click this link https://boot.dev/?promo=VERITASIUM and use our code VERITASIUM to get 25% off your first payment for boot.dev. If you’re looking for a molecular modelling kit, try Snatoms, a kit I invented where the atoms snap together magnetically - https://ve42.co/SnatomsV Sign up for the Veritasium newsletter for weekly science updates - https://ve42.co/Newsletter For those curious about the path-count estimate: we estimated the non-backtracking paths NYC→SF, using a sparse spatial network model with mean degree ≈ 2.5 and characteristic length ≈ √N. ▀▀▀ 0:00 What is a ‘shortest path algorithm’? 3:30 Dijkstra’s 20 Minute Algorithm 6:30 The First Route Planner 10:31 A* Search Algorithm 12:40 Shortest Doesn’t Mean Fastest 15:08 Road Network Hierarchy 18:29 Mapping North America - Nested Dissection 25:17 How do map apps work? 28:04 Simplicity is prerequisite for reliability ▀▀▀ Check out @twoswap's channel for some fantastic videos! A big thank you to Ben Strasser and Julian Dibbelt who were incredibly gracious with their time and feedback. Thank you to all the experts we interviewed for this video: Aaron Bernstein, Tim Roughgarden, Tomas Rokicki, Jon Kleinberg, Virginia Vassilevska Williams, Peter Sanders, and the team behind the SSSP Barrier Paper: Xinkai Shu, Ran Duan, Xiao Mao, Longhui Yin, Jiayi Mao For more information on how you choose A*'s heuristic, check out Polylog's video: https://youtu.be/A60q6dcoCjw?si=5LHOmZ8ZKvR_kLcx If you'd like more information on Minecraft's A*, check out RedLogic's video: https://youtu.be/Zg0Cxn8AVZA?si=DyECX4wmeuSb4c1n ▀▀▀ References: https://ve42.co/DijkstraRefs ▀▀▀ Special thanks to our Patreon supporters: Adam Foreman, Albert Wenger, Alex Porter, Alexander Tamas, André Powell, Anton Ragin, Balkrishna Heroor, Bertrand Serlet, Blake Byers, Bruce, Bryan Ackermann, Chris Brewer, Data Don, Dave Kircher, David Johnston, David Tseng, EJ Alexandra, Evgeny Skvortsov, Garrett Mueller, Gnare, gpoly, Hayden Christensen, Hong Thai Le, Ibby Hadeed, Jeromy Johnson, Jesse Brandsoy, Juan Benet, Kelcey Steele, KeyWestr, Kyi, Lee Redden, Marinus Kuivenhoven, Mark Heising, Martin Paull, Meekay, meg noah, Michael Krugman, Moebiusol - Cristian, Orlando Bassotto, Parsee Health, Paul Peijzel, Richard Sundvall, Robson, Sam Lutfi, Shalva Bukia, Sinan Taifour, Tj Steyn, Ubiquity Ventures, Vahe Andonians, wolfee ▀▀▀ Writers: Sulli Yost Producer & Director: Sulli Yost Presenter: Henry van Dyck & Derek Muller Editor: Jonny Lennard and Trenton Oliver Additional Editor: James Stuart Camera Operators: Sulli Yost & Henry van Dyck Illustrators: Jakub Misiek & Maria Gusakovich Animators: @twoswap, Andrew Neet, Jonny Lennard, Alex Drakoulis & Fabio Albertelli Researchers: Aakash Singh Bagga & Callum Cuttle Thumbnail Designers: Abdallah Rabah, Ren Hurley, Ben Powell & Daniel Ellacott Production Team: Jess Bishop-Laggett, Glen Griffiths, Matthew Cavanagh & Anna Milkovic Executive Producers: Casper Mebius, Gregor Čavlović & Derek Muller Map data © OpenStreetMap contributors, available under the Open Database License: https://www.openstreetmap.org/copyright Additional video/photos supplied by Getty Images and Pond5 Music from Epidemic Sound

If there's a hotel with infinite rooms, could it ever be completely full? Could you run out of space to put everyone? The surprising answer is yes -- this is important to know if you're the manager of the Hilbert Hotel.

You and 3 amigos are buried neck deep in sand in a prison yard. The guard says if one of you can guess your own hat colour you can all go free. You know there are two black hats and two white hats and you can only see the hats of the people in front of you. A minute passes in silence and then one of you shouts out a correct answer. Who shouted? A, B, C or D?

AD How many batteries would it take to power a human? We partnered with @AnkerOfficial to find out... Pick up your Anker Prime power bank here: https://ankerfast.club/noagy5 #AnkerTech #Anker #AnkerPrime #Veritasium #Tech

In the 1970s, Intel couldn't work out what was damaging the DRAM on their microchips. The cause turned out to be the ceramic that the chip was encased in. It was secretly flipping 1s to 0s. But how?

How does a sewing machine work? The answer is more genius than you might think.

Is the CIA’s Ghost Murmur technology real? Sponsored by Ground News. Go to https://ground.news/Ve for 40% off the unlimited Vantage plan. If you’re looking for a molecular modelling kit, try Snatoms, a kit I invented where the atoms snap together magnetically - https://ve42.co/SnatomsV Sign up for the Veritasium newsletter for weekly science updates - https://ve42.co/Newsletter ▀▀▀ A huge thanks to Patrick Maletinsky at the University of Basel and Jan Jeske at the Fraunhofer Institute for their insights into NV magnetometry. Likewise, thank you to Brad Roth at Oakland University, John Wikswo at Vanderbilt University, and Bob Fagaly at the IEEE for their input on the history and constraints of magnetometry. Thank you to Douglas London, CIA Senior Operations Officer (Rtd), for his input on the story. His book, The Recruiter, can be found here - https://ve42.co/Recruiter A big thanks to Herbert Lin at Stanford University and Emma Briant at the University of Notre Dame for their knowledge on deception and propaganda tactics. ▀▀▀ References Exclusive | 'Ghost Murmur' via the New York Post Exclusive | Trump confirms CIA 'Ghost Murmur' tool via the New York Post Béchard, D. E. (2026). Scientists question CIA’s claim of long-range heartbeat detection. Scientific American. Roth, B. J. (2023). Biomagnetism: The First Sixty Years. Sensors Doherty, M. W. et al. (2013). The nitrogen-vacancy colour centre in diamond. Physics Reports. "Quantum Diamond Sensing: The Surprising Power of NV Centers | Ron Walsworth" by 632nm Podcast on YouTube "Ronald Walsworth - “Quantum Diamond Sensors" by Stanford Physics on YouTube Arai, K. et al. (2022). Millimetre-scale magnetocardiography of living rats with thoracotomy. Communications Physics. Additional sources available here: Ghost Murmur Video - https://ve42.co/ReferencesGhost Images & Video: https://www.youtube.com/watch?v=WmXuaHX3QeY https://www.youtube.com/watch?v=DkmHh6eZoZs https://www.youtube.com/watch?v=vrRJimixWEc ▀▀▀ Special thanks to our Patreon supporters: Adam Foreman, Albert Wenger, Alex Porter, Alexander Tamas, André Powell, Anton Ragin, Balkrishna Heroor, Bertrand Serlet, Blake Byers, Bruce, Bryan Ackermann, Cartier, Chris Brewer, Daniel Martins, Data Don, Dave Kircher, David Johnston, David Tseng, EJ Alexandra, Evgeny Skvortsov, Garrett Mueller, Gnare, gpoly, Hayden Christensen, Hong Thai Le, Ibby Hadeed, Jeromy Johnson, Jesse Brandsoy, Juan Benet, Kelcey Steele, KeyWestr, Kyi, Lee Redden, Marinus Kuivenhoven, Mark Heising, Martin Paull, Meekay, meg noah, Michael Krugman, Orlando Bassotto, Parsee Health, Paul Peijzel, Richard Sundvall, Robson, Sam Lutfi, Shalva Bukia, Sinan Taifour, Tj Steyn, Ubiquity Ventures, Vahe Andonians, William Yoon, wolfee ▀▀▀ Writer: Gregor Čavlović Producer and Director: Gregor Čavlović Presenter: Gregor Čavlović Editors: Jack Saxon and James Stuart Additional Editor: James Horsley Animators: Emma Wright, Fabio Albertelli, and Domonkos Józsa Researchers: Aakash Singh Bagga Production Team: Jess Bishop-Laggett, Glen Griffiths, Matthew Cavanagh & Anna Milkovic Executive producer: Casper Mebius Thumbnail contributions by Abdallah Rabah, Ren Hurley, and Ben Powell Additional video/photos supplied by Getty Images and Pond5 Music from Epidemic Sound

The crystals that wiped out an HIV medication, almost overnight. Thanks to SoFi for sponsoring the video! Click here to sign-up for SoFi Checking and Savings: https://sofi.com/ve In 2025, we launched the Elements of Truth game on Kickstarter and were thrilled by the response. We’re now in the final stages of production, with Kickstarter rewards shipping soon. If you missed the campaign, you can now pre-order the retail edition through our new website here -https://ve42.co/PolymorphsDesc If you’re looking for a molecular modelling kit, try Snatoms, a kit I invented where the atoms snap together magnetically - https://ve42.co/SnatomsV Sign up for the Veritasium newsletter for weekly science updates - https://ve42.co/Newsletter ▀▀▀ Check out the excellent video by Reactions here: https://youtu.be/PccOwGEbtQU?si=NOpmaulDcoq6Kif- This video was a huge collaborative effort! Special thanks to… Dr Andreas Kafizas for all his help with the Silver and Tin demonstrations, and staying up for those 14 hours with us monitoring the timelapse! As well as Conrad Duncan and the team at Imperial College London. @ChrisYoungCooks for teaching Casper how to temper chocolate and @jameshoffmann and the team for letting us take over their studio; we had a great day! Many thanks to Professor Adam Matzger, Professor Katharina Fromm and Professor Mike Zaworotko for taking the time to talk to us. Also thank you to Dr. William McVicker and the British Institute of Organ Studies and Chris at Luciteria Science for helping us source our grey and white tin samples. Correction: 11:45 should say carbon-nitrogen triple bond not double bond ▀▀▀ 0:00 The Disease Infecting Miracle Medicine 4:20 An Explosive Feud 10:05 How The Same Compound Can Behave Two Different Ways 13:18 Polymorphs Of Chocolate 19:51 Why Ritonavir Stopped Working 22:57 The Tin Pest 27:28 Disappearing Polymorphs 30:20 Is Everything Polymorphic? ▀▀▀ References can be found here - https://ve42.co/PolymorphRefs ▀▀▀ Special thanks to our Patreon supporters: Adam Foreman, Albert Wenger, Alex Porter, Alexander Tamas, André Powell, Anton Ragin, Balkrishna Heroor, Bertrand Serlet, Blake Byers, Bruce, Bryan Ackermann, Cartier, Chris Brewer, Daniel Martins, Data Don, Dave Kircher, David Johnston, David Tseng, EJ Alexandra, Evgeny Skvortsov, Garrett Mueller, Gnare, gpoly, Hayden Christensen, Hong Thai Le, Ibby Hadeed, Jeromy Johnson, Jesse Brandsoy, Juan Benet, Kelcey Steele, KeyWestr, Kyi, Lee Redden, Marinus Kuivenhoven, Mark Heising, Martin Paull, Meekay, meg noah, Michael Krugman, Orlando Bassotto, Parsee Health, Paul Peijzel, Richard Sundvall, Robson, Sam Lutfi, Shalva Bukia, Sinan Taifour, Tj Steyn, Ubiquity Ventures, Vahe Andonians, William Yoon, wolfee ▀▀▀ Writers: Gabe Strong & Casper Mebius Producer and Director: Gabe Strong Presenters: Derek Muller & Casper Mebius Editor: Trenton Oliver Assistant Editor: James Stuart Art Director: Mathias Hawk Illustrators: Jakub Misiek, Emma Wright, Maria Gusakovich & Raphael Aubry Animators: Fabio Albertelli, Andrew Neet, Emma Wright & Alex Drakoulis Researcher: Sophia Rose Additional Research: Callum Cuttle Camera Operators: Rob Newman, Casper Mebius, Gabe Strong, Callum Cuttle & Derek Muller Voice-over Artist: Gregor Čavlović Thumbnail Designers: Abdallah Rabah, Ren Hurley & Ben Powell Production Team: Jess Bishop-Laggett, Glen Griffiths, Mathew Cavanagh & Anna Milkovic Executive Producers: Derek Muller, Casper Mebius & Gregor Čavlović Additional video/photos supplied by Getty Images & Storyblocks Music from Epidemic Sound