Did you know that many everyday objects around you hide secret features you’ve never noticed? From the button on a seat belt to the hole in a pen cap or even the extra eyelets on your sneakers, these small details all have hidden purposes that make life easier, safer, or just more interesting. In this video, we explore the most surprising hidden purposes of everyday items you use all the time without thinking. Some of these secret features were designed for safety, some for convenience, and others are clever engineering tricks that most people completely miss. Once you see them, you’ll never look at ordinary objects the same way again. If you’ve ever wondered what those tiny symbols, holes, buttons, or shapes are really for, this video will finally give you the answers.
Animation is created by Bright Side.
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Check our Bright Side podcast on Spotify and leave a positive review! https://open.spotify.com/show/....0hUkPxD34jRLrMrJux4V
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Think you’ve got sharp instincts? These riddles are packed with hidden dangers, and your job is to spot them before it’s too late. From suspicious strangers to traps disguised as safe choices, each puzzle will test how quickly you can think under pressure. Some answers might seem obvious—but the real danger is always lurking where you least expect it. Challenge yourself, compete with your friends, and see who’s clever enough to survive every scenario. Hit play now, and let’s find out if you can outsmart danger before it catches you.

Animation is created by Bright Side.
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Music from TheSoul Sound: https://thesoul-sound.com/

Check our Bright Side podcast on Spotify and leave a positive review! https://open.spotify.com/show/....0hUkPxD34jRLrMrJux4V
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This video is made for entertainment purposes. We do not make any warranties about the completeness, safety and reliability. Any action you take upon the information in this video is strictly at your own risk, and we will not be liable for any damages or losses. It is the viewer's responsibility to use judgement, care and precaution if you plan to replicate.

In this Season 2 Trafficked with Mariana van Zeller mega episode compilation, Mariana van Zeller takes us into the hidden world of black market trade. Featuring five full episodes:

Black Market Surgery
Mariana van Zeller investigates underground plastic surgery, from motel-room operations to a deadly revelation about Miami’s discount surgery centers.

Romance Scams
Mariana journeys from America’s heartland to the cafes of Ghana to meet the romance scammers fleecing Americans out of millions.

Black Market Marijuana
Mariana sets off on a wild journey through California’s black market for weed, which has mushroomed since marijuana legalization four years ago.

Outlaw Motorcycle Clubs
Mariana van Zeller investigates outlaw motorcycle gangs known as 1% clubs, learning about the bonds of brotherhood that fuel these violent groups.

Meth
Mariana van Zeller follows a meth superhighway from a cartel-run lab in Sinaloa across the border and into the lives of American users.

Trafficked with Mariana Van Zeller | S2, E1 - 5

Watch more Trafficked with Mariana van Zeller on Disney+: https://on.natgeo.com/4gDKpAI

Explore the World with National Geographic subscriptions: https://natgeo.com/ytngmagazine

➡ Subscribe: https://on.natgeo.com/4p5A0D6
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And check out more National Geographic series and specials here:
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➡ Hulu: https://on.natgeo.com/3Qor0Ko
➡ NGTV: https://natgeo.com/tv
➡ ABC: https://abc.com

#MegaEpisode #TraffickedWithMarianaVanZeller #NationalGeographic

About National Geographic:
National Geographic is the world's premium destination for critically acclaimed storytelling around science and exploration. Discover amazing wildlife, ancient civilizations, hidden worlds, and the incredible wonders of our Earth. Through world-class scientists, photographers, journalists, and filmmakers, Nat Geo inspires fans of all ages to connect with, explore, and care about the world.

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Investigating Black Market Ventures | Trafficked Season 2 MEGA EPISODE | National Geographic
https://youtu.be/wAOMeo-DiiA

National Geographic
youtube.com/natgeo

Heisenberg's uncertainty principle tells us that it is impossible to simultaneously measure the position and momentum of a particle with infinite precision. In our everyday lives we virtually never come up against this limit, hence why it seems peculiar. In this experiment a laser is shone through a narrow slit onto a screen. As the slit is made narrower, the spot on the screen also becomes narrower. But at a certain point, the spot starts becoming wider. This is because the photons of light have been so localised at the slit that their horizontal momentum must become less well defined in order to satisfy Heisenberg's uncertainty principle.

I based this video on one by Prof. Walter Lewin of MIT: http://bit.ly/100Wk2K

Henry (MinutePhysics) has previously made a video about Heisenberg's Uncertainty Principle where he treats it as less spooky and more a consequence of waves: http://bit.ly/TV3xO5

Sixty Symbols has a great video on Planck's constant: http://bit.ly/11upebY

Thanks to the University of Sydney for hosting this experiment, especially to Tom and Ralph for their assistance getting it working.

Music: Kevin McLeod (Incompetech.com) Mirage and Danse Macabre

Complete unedited interviews: http://www.youtube.com/watch?v=8dcw98B2Nzg
Trees can weigh hundreds or even thousands of tons, but where do they get this mass from? A few common answers are: the soil, water, and sunlight. But the truth is the vast majority of a dry tree's mass comes from the air - it originated as carbon dioxide

Kodak detected the first atomic bomb before anyone else figured it out. Then they made a deal not to tell anyone. Thanks to HBO Max, and their new show raised by Wolves for sponsoring this video! https://rb.gy/alghwn

Thanks to Uranium: Twisting the Dragon's Tail for the opening clip: https://www.pbs.org/show/urani....um-twisting-dragons-

References:
Albuquerque Tribune Bulletin, July 16, 1945 – https://www.marshallfoundation.....org/library/documen

Webb, J. H. (1949). The fogging of photographic film by radioactive contaminants in cardboard packaging materials. Physical Review, 76(3), 375.

Julian Webb at Oak Ridge – Snavely, B. B. (1989). Julian H. Webb. PhT, 42(7), 87.https://physicstoday.scitation.....org/doi/pdf/10.1063

Radium in watch dials – https://www.epa.gov/radtown/radioactivity-antiques

A 1958 video about how Kodak film is made, noting the careful monitoring of radioactive contaminants – https://www.youtube.com/watch?v=9qjBJOFImaU&t=597s&ab_channel=OwenMorgan

Radioactive fallout in 1951 - https://www.nytimes.com/1951/0....2/03/archives/increa

1998 senate hearing – https://www.govinfo.gov/conten....t/pkg/CHRG-105shrg44

Institute of Medicine and National Research Council. 1999. Exposure of the American People to Iodine-131 from Nevada Nuclear-Bomb Tests: Review of the National Cancer Institute Report and Public Health Implications. Washington, DC: The National Academies Press. https://doi.org/10.17226/6283. https://www.cancer.gov/about-c....ancer/causes-prevent

Baby Teeth Survey – Reiss, L. Z. (1961). Strontium-90 absorption by deciduous teeth. Science, 134(3491), 1669-1673.

Strontium 90 and Cancer rates – Gould, J. M., Sternglass, E. J., Sherman, J. D., Brown, J., McDonnell, W., & Mangano, J. J. (2000). Strontium-90 in deciduous teeth as a factor in early childhood cancer. International Journal of Health Services, 30(3), 515-539.

Wine forensics – Hubert, P., Perrot, F., Gaye, J., Médina, B., & Pravikoff, M. S. (2009). Radioactivity measurements applied to the dating and authentication of old wines. Comptes Rendus Physique, 10(7), 622–629. doi:10.1016/j.crhy.2009.08.007

Strontium 90 in forensics – Maclaughlin-Black, S. M., Herd, R. J., Willson, K., Myers, M., & West, I. E. (1992). Strontium-90 as an indicator of time since death: a pilot investigation. Forensic science international, 57(1), 51-56.

Research and Writing by Derek Muller, Petr Lebedev, and Jonny Hyman

Filmed and edited by Derek Muller
Animations by Ivy Tello and Jonny Hyman
Music by Jonny Hyman
Additional Music from:
Epidemic Sound https://epidemicsound.com "Seaweed"
Kevin MacLeod https://incompetech.com "Lightless dawn"
Craig Conrad https://www.craigconard.com/royaltyfree "ASTRAL"

Made for ABC TV Catalyst http://www.abc.net.au/catalyst/ as an extended version of my Comparing Temperatures video: http://www.youtube.com/watch?v=hNGJ0WHXMyE

We experimented to see how much pain our volunteers could handle. Go to https://headspace-web.app.link/e/vstm to try Headspace for free using the code VERITASIUM

Studies on Headspace - https://ve42.co/Headspace

A massive thank you to Rayner Moss for recreating the experiment equipment and making this shoot happen.

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Special thanks to our Patreon supporters! Join the community to help us keep our videos free, forever: https://ve42.co/PatreonDE

Adam Foreman, Anton Ragin, Balkrishna Heroor, Bertrand Serlet, Bill Linder, Blake Byers, Bruce, Burt Humburg, Dave Kircher, David Johnston, Evgeny Skvortsov, Garrett Mueller, Gnare, gpoly, I. H., John H. Austin, Jr., John Kiehl, Josh Hibschman, Juan Benet, KeyWestr, Kyi, Lee Redden, Marinus Kuivenhoven, Matthias Wrobel, Max Paladino, Meekay, Meg Noah, Michael Krugman, Name, Orlando Bassotto, Paul Peijzel, Richard Sundvall, Sam Lutfi, Stephen Wilcox, Tj Steyn, Toni, TTST, Ubiquity Ventures, Wolfee.

If you’re looking for a molecular modeling kit, try Snatoms, a kit I invented where the atoms snap together magnetically - https://ve42.co/SnatomsV

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References:
Kahneman, D. et al. (1993). When More Pain Is Preferred to Less: Adding a Better End. Psychological Science - https://ve42.co/Kahneman1993
Kahneman, D. (2011). Thinking, fast and slow. Farrar, Straus and Giroux - https://ve42.co/FastAndSlow
Fredrickson, B. L., Kahneman, D. (1993). Duration neglect in retrospective evaluations of affective episodes. Journal of personality and social psychology - https://ve42.co/Fredrickson1993
Kahneman, D., Tversky, A. (1972). Subjective probability: A judgment of representativeness. Cognitive Psychology - https://ve42.co/Kahneman1972
Diener, E. et al. (2001). End Effects of Rated Life Quality: The James Dean Effect. Psychological Science - https://ve42.co/Deiner2001
Redelmeier, D. A. et al. (2003). Memories of colonoscopy: a randomized trial. Pain - https://ve42.co/Redelmeier2003
Kemp, S. et al. (2008). A test of the peak-end rule with extended autobiographical events. Memory & Cognition - https://ve42.co/Kemp2008

Images & Video:
Daniel Kahneman via UNSW - https://ve42.co/ImgKahneman
Barbara Fredrickson via UNC - https://ve42.co/ImgFredrickson
Stephen Gould via achievement.org - https://ve42.co/ImgGould
Amos Tversky via LGT - https://ve42.co/ImgTversky

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Directed by Petr Lebedev
Written by Petr Lebedev and Derek Muller
Edited by Peter Nelson
Animated by Fabio Albertelli and Ivy Tello
Illustrated by Jakub Misiek
Filmed by Derek Muller and Bernard Lau
Produced by Petr Lebedev, Derek Muller, Rob Beasley Spence, Owen Maher, David Szasz, Emily Taylor, Gregor Čavlović and Alistair Dann

Thumbnail contributions by Ren Hurley and Peter Sheppard

Additional video/photos supplied by Getty and Storyblocks
Music from Epidemic Sound

Why does superglue always stick to your hands and never what you want it to? Get a little smarter every day with Brilliant. Visit https://brilliant.org/veritasium for a 30-day free trial and 20% off your annual premium subscription.

A heartfelt thank you to Dr. Allison Christy and Dr. John Bobo for their invaluable expertise, fresh perspectives, and explanations.
Thank you to Emily Von Stein and Chris Masahiro at Aron Alpha, Dr. Chantelle Champagne, and Dr. Rohit Gupta for their time and contributions to the initial research that laid the groundwork for this project.

Try Snatoms! A molecular modelling kit I invented where the atoms snap together.
https://ve42.co/SnatomsV

Sign up to the Veritasium newsletter for weekly science updates - https://ve42.co/Newsletter

ANIMATION CORRECTION:
At 4:52, the negative charge should be drawn on the carbon at the end of the chain, not on the second to last carbon. This also holds during the polymerization process (5:15), where the negative charge should move right to the end of the chain.

▀▀▀
0:00 The Invention of Super Glue
2:43 How Does Super Glue Work?
5:38 How To Get Superglue Off Your Skin
8:33 Why Is Super Glue So Strong?
12:00 Why Doesn’t Super Glue Work on plastic?
13:45 Mixing Super Glue and Baking Soda
15:30 Using Super Glue Underwater
15:59 Super Glue On Wounds
19:47 A Solution To Microplastics?

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References and Credits:


Dr. Harry Coover Jr. (Nov 2023) via Sutori - https://ve42.co/sutori
Allison Christy, Closed-loop recyclable plastics from poly(ethyl cyanoacrylate) - https://www.science.org/doi/10.1126/sciadv.adg2295
About Cyanoacrylate Adhesives. via Permabond - https://ve42.co/permab
Kodak Eastman In Wikipedia - https://ve42.co/kodakw
Harry Coover and the Invention of Super Glue. (Mar 2022) via SciHi Blog - https://ve42.co/scihio
Humphrey Sam Samuel (May 2024). Cyanoacrylate Chemistry and Polymerization Mechanisms. - https://ve42.co/pcbioc
Radical polymerization.. In Wikipedia - https://ve42.co/wikira
Overview of materials for Cyanoacrylate Adhesive. via MATWEBb - https://ve42.co/matweb
United States Patent Office: US2776232. (Jan 1957) via US patent office - https://ve42.co/patentb
Medical Grade Cyanoacrylate Adhesive Market Size Growth Report. (Nov 2024) via Linkedin - https://ve42.co/linkpu
Science Channel. (Dec 2017). Think Super Glue Can Lift A Pickup Truck? via Youtube - https://ve42.co/ytbpee
Loctite & Teroson UK. (Apr 2023). Learn How Loctite SF 7452 Can Accelerate Bonding When using Loctite 454 via Youtube - https://ve42.co/loctiteg

Image and Video Credits
LOCTITE® North America. (May 2017). Loctite 4902FL Highly Flexible Cyanoacrylate via Youtube - https://ve42.co/loctitef
The Gorilla Glue Company. (May 2021). How To Use Gorilla Super Glue via Youtube - https://ve42.co/gluehowt
Flex Seal. (Nov 2022). Flex Super Glue Commercial - The Flex Seal Family of Products via Youtube - https://ve42.co/flexglue
ewjxn. (Nov 2020). 1984 Instant Krazy Glue Strong enough to hold this woman TV Commercial.mp4 via Youtube - https://ve42.co/krazyglue
tvdays. (Nov 2007). ELMERS GLUE 1960.mp4 via Youtube - https://ve42.co/elmer
Aron Alpha Industrial Krazy Glue. (Feb 2024). The Leader in High Performance Instant Adhesives via Youtube - https://ve42.co/aronalpha
How researchers turned superglue into a cheap plastic alternative by via fastcompany - https://ve42.co/superplastic
Woman Mistakenly Uses Glue Instead Of Eye Drops by via CBS News - https://ve42.co/eyegludd

Further References: https://ve42.co/refsuperglue


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Special thanks to our patrons for sticking around!

Adam Foreman, Albert Wenger, Alexander Tamas, Anton Ragin, Autodidactic Studios, Bertrand Serlet, Blake Byers, Bruce, Dave Kircher, David Johnston, Evgeny Skvortsov, Farbod Mansorian, Garrett Mueller, Gnare, gpoly, Greg Scopel, I. H., Juan Benet, KeyWestr, Kyi, Lee Redden, Marinus Kuivenhoven, Matthias Wrobel, Meekay, meg noah, Michael Krugman, Orlando Bassotto, Paul Peijzel, Richard Sundvall, Sam Lutfi, Spilmann Reed, TTST, Tj Steyn, Ubiquity Ventures, wolfee

Join us on Patreon for early access videos, bonus content, and to support Veritasium! https://ve42.co/PatreonDE

Live on Patreon now is an exclusive unseen interview with Chantelle Champagne https://www.patreon.com/posts/121045719

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Directed by Sulli Yost
Written by Sulli Yost and Derek Muller
Edited by Peter Nelson
Assistant Editor - James Stuart
Illustrated by Jakub Misiek and Caine Esperanza
Animated by Emma Wright, Andrew Neet and Fabio Albertelli
Filmed and demos done by Sulli Yost, Derek Muller and Wylie Overstreet
Additional research by Geeta Thakur
Produced by Sulli Yost, Derek Muller, Rob Beasley Spence and Tori Brittain
Thumbnail contributions by Ren Hurley, Peter Sheppard, Ben Powell
Additional video/photos supplied by Getty Images, Storyblocks
Music from Epidemic Sound and Jonny Hyman

Chaos theory means deterministic systems can be unpredictable. Thanks to LastPass for sponsoring this video. Click here to start using LastPass: https://ve42.co/VeLP
Animations by Prof. Robert Ghrist: https://ve42.co/Ghrist

Want to know more about chaos theory and non-linear dynamical systems? Check out: https://ve42.co/chaos-math

Butterfly footage courtesy of Phil Torres and The Jungle Diaries: https://ve42.co/monarch
Solar system, 3-body and printout animations by Jonny Hyman
Some animations made with Universe Sandbox: https://universesandbox.com/
Special thanks to Prof. Mason Porter at UCLA who I interviewed for this video.

I have long wanted to make a video about chaos, ever since reading James Gleick's fantastic book, Chaos. I hope this video gives an idea of phase space - a picture of dynamical systems in which each point completely represents the state of the system. For a pendulum, phase space is only 2-dimensional and you can get orbits (in the case of an undamped pendulum) or an inward spiral (in the case of a pendulum with friction). For the Lorenz equations we need three dimensions to show the phase space. The attractor you find for these equations is said to be strange and chaotic because there is no loop, only infinite curves that never intersect. This explains why the motion is so unpredictable - two different initial conditions that are very close together can end up arbitrarily far apart.

Music from https://epidemicsound.com "The Longest Rest" "A Sound Foundation" "Seaweed"

Have your voice heard at the UN Climate Summit in NYC, September 23: http://bit.ly/WhyNotVe



Interview filming by Chris Cassella: http://bit.ly/ScienceAlertVe

How were the first computers made? Head to https://brilliant.org/veritasium to start your free 30-day trial, and the first 200 people get 20% off an annual premium subscription.

A huge thanks to David Lovett for showing me his awesome relay and vacuum tube based computers. Check out his YouTube channel @UsagiElectric

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References:
Herring, C., & Nichols, M. H. (1949). Thermionic emission. Reviews of modern physics, 21(2), 185. – https://ve42.co/Herring1949

Goldstine, H. H., & Goldstine, A. (1946). The electronic numerical integrator and computer (eniac). Mathematical Tables and Other Aids to Computation, 2(15), 97-110. – https://ve42.co/ENIAC

Shannon, C. E. (1938). A symbolic analysis of relay and switching circuits. Electrical Engineering, 57(12), 713-723. – https://ve42.co/Shannon38

Boole, G. (1847). The mathematical analysis of logic. Philosophical Library. – https://ve42.co/Boole1847

The world’s first general purpose computer turns 75 – https://ve42.co/ENIAC2

Dylla, H. F., & Corneliussen, S. T. (2005). John Ambrose Fleming and the beginning of electronics. Journal of Vacuum Science & Technology A: Vacuum, Surfaces, and Films, 23(4), 1244-1251. – https://ve42.co/Dylla2005

Stibitz, G. R. (1980). Early computers. In A History of Computing in the Twentieth Century (pp. 479-483). Academic Press.

ENIAC’s Hydrogen Bomb Calculations – https://ve42.co/ENIAC3


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Special thanks to our Patreon supporters:
Emil Abu Milad, Tj Steyn, meg noah, Bernard McGee, KeyWestr, Amadeo Bee, TTST, Balkrishna Heroor, John H. Austin, Jr., john kiehl, Anton Ragin, Benedikt Heinen, Diffbot, Gnare, Dave Kircher, Burt Humburg, Blake Byers, Evgeny Skvortsov, Meekay, Bill Linder, Paul Peijzel, Josh Hibschman, Mac Malkawi, Juan Benet, Ubiquity Ventures, Richard Sundvall, Lee Redden, Stephen Wilcox, Marinus Kuivenhoven, Michael Krugman, Cy ‘kkm’ K’Nelson, Sam Lutfi.

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Written by Petr Lebedev, Derek Muller and Kovi Rose
Edited by Trenton Oliver
Animated by Mike Radjabov, Ivy Tello and Fabio Albertelli
Filmed by Derek Muller & Raquel Nuno
Additional video/photos supplied by Getty Images & Pond5
Music from Epidemic Sound
Produced by Derek Muller, Petr Lebedev, & Emily Zhang
Thumbnail by Ignat Berbeci

Want more awesome HD slow-mo? http://www.youtube.com/watch?v=uiyMuHuCFo4
Slinky not long enough? Click here: http://www.youtube.com/watch?v=JsytnJ_pSf8
How does a slinky fall when extended by its own weight and then released? We discover the surprising answer using a slow motion camera that records 300 frames per second. Answer link: http://www.youtube.com/watch?v=oKb2tCtpvNU

For a great explanation, check out Rhett Allain's analysis here: http://www.wired.com/wiredscie....nce/2011/09/modeling

This is an image of the supermassive black hole, Sagittarius A*, at the center of our Milky Way galaxy.
Visit https://www.kiwico.com/veritasium30 to get 30% off your first month of any crate!

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Image of Sgr A* from EHT collaboration
Event Horizon Telescope collaboration: https://ve42.co/EHT

Animations from The Relativistic Astrophysics group, Institute for Theoretical Physics, Goethe-Universität Frankfurt. Massive thanks to Prof. Luciano Rezzolla, Dr Christian Fromm and Dr Alejandro Cruz-Osorio.

A huge thanks to Prof. Peter Tuthill and Dr Manisha Caleb for feedback on earlier versions of this video and helping explain VLBI.

Great video by Thatcher Chamberlin about VLBI here – https://youtu.be/Y8rAHTvpJbk

Animations and simulations with English text:
L. R. Weih & L. Rezzolla (Goethe University Frankfurt)
https://youtu.be/jvftAadCFRI

Video of stars going around Sgr A* from European Southern Observatory
https://www.eso.org/public/videos/eso1825e/

Video zooming into the center of our galaxy from European Southern Observatory
https://www.youtube.com/watch?v=dXAU0gzsPOw

Video of observation of M87 courtesy of:
C. M. Fromm, Y. Mizuno & L. Rezzolla (Goethe University Frankfurt)
https://youtu.be/meOKmzhTcIY

Video of observation of SgrA* courtesy of
C. M. Fromm, Y. Mizuno & L. Rezzolla (Goethe University Frankfurt)
Z. Younsi (University College London)
https://youtu.be/VnsZj9RvhFU

Video of telescopes in the array 2017:
C. M. Fromm & L. Rezzolla (Goethe University Frankfurt)
https://youtu.be/Ame7fzBuFnk

Animations and simulations (no text):
L. R. Weih & L. Rezzolla (Goethe University Frankfurt)
https://youtu.be/XmvpKFSvB7A


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Special thanks to Patreon supporters: Inconcision, Kelly Snook, TTST, Ross McCawley, Balkrishna Heroor, Chris LaClair, Avi Yashchin, John H. Austin, Jr., OnlineBookClub.org, Dmitry Kuzmichev, Matthew Gonzalez, Eric Sexton, john kiehl, Anton Ragin, Diffbot, Micah Mangione, MJP, Gnare, Dave Kircher, Burt Humburg, Blake Byers, Dumky, Evgeny Skvortsov, Meekay, Bill Linder, Paul Peijzel, Josh Hibschman, Mac Malkawi, Michael Schneider, jim buckmaster, Juan Benet, Ruslan Khroma, Robert Blum, Richard Sundvall, Lee Redden, Vincent, Stephen Wilcox, Marinus Kuivenhoven, Clayton Greenwell, Michael Krugman, Cy 'kkm' K'Nelson, Sam Lutfi, Ron Neal

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Written by Derek Muller
Animation by Ivy Tello, Mike Radjabov, Maria Raykova
Thumbnail by Ignat Berbeci
Filmed by Petr Lebedev

The best and worst predictions in science are both based on the same underlying physics
Check out the Great Courses Plus: http://ow.ly/cePe303oKDM
Support Veritasium on Patreon: http://bit.ly/VePatreon

Special thanks to:
Prof. Sean Carroll
Prof. Brian Schmidt
Prof. Stephen Bartlett
Prof. Geraint Lewis

More on this topic: http://wke.lt/w/s/XDkwi

Patreon supporters:
Bryan Baker, Donal Botkin, Tony Fadell, Jason Buster, Saeed Alghamdi, Nathan Hansen

Virtual particles are a way of talking about fields and their interactions as though particles are doing all the work. This is why there is some controversy around using the term 'virtual particles'. Some people think the term is useful, especially since in calculating with Feynman diagrams you draw all the particle interactions that are possible (and then do the calculations to get the right answer). While others feel this terminology is misleading because virtual particles don't behave like real particles and can't be observed.

A UCLA Physics Professor bet me $10,000 that my video about going downwind faster than the wind was wrong. This video is sponsored by Brilliant. The first 200 people to sign up via https://brilliant.org/veritasium get 20% off a yearly subscription.

For more information about the Veritasium Science Communication Contest check out -- https://ve42.co/contest

▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀
The wager agreement: https://ve42.co/wager

Prof. Kusenko's slides: https://ve42.co/Kusenko

My rebuttal: https://ve42.co/rebuttal
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Huge thanks to Xyla Foxlin for building the model cart, and making the instructions so accessible to the public. Check out Xyla's video -- https://youtu.be/VUgajGv4Aok

A massive thanks to Bill Nye, Neil DeGrasse Tyson, and Sean Carroll for witnessing the signing of the wager.

A huge thanks to Prof. Alexander Kusenko for being a man of honour -- it's a difficult thing to change your mind, especially in a public forum.

A huge thanks to Prof. Mark Drela for the interview and help making sure we got the physics right.

A massive thanks to Rick Cavallaro for making Blackbird, all your insights, analysis, data, and general help with these videos -- it was so fun to work with you on this crazy project -- check out Rick's channel https://ve42.co/Rick

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References
M. Drela. Dead-Downwind Faster Than The Wind (DDWFTTW)
Analysis (Jan 2009) -- https://ve42.co/Drela

2013 AAPT United States Physics Olympiad Semifinal Exam -- https://ve42.co/AAPT2013

Rick's treadmill footage -- https://ve42.co/Treadmill

Rick's multiple explanations of how Blackbird works -- https://ve42.co/DDWFTTW

Blackford, B. L. (1978). The physics of a push‐me pull‐you boat. American Journal of Physics, 46(10), 1004-1006. — https://ve42.co/Blackford1979

Ruina corrects errors in the above paper: http://ruina.tam.cornell.edu/r....esearch/topics/misce

Forum discussions -- https://ve42.co/forum Blog -- https://ve42.co/blog1 and retraction https://ve42.co/BlogRetraction

Bauer, A. B. (1969, April). Faster than the Wind. In First AIAA Symposium on Sailing. -- https://ve42.co/Bauer1969

Bauer's Obituary -- https://ve42.co/BauerObituary

Gaunaa, M., Øye, S., & Mikkelsen, R. F. (2009). Theory and design of flow driven vehicles using rotors for energy conversion. In EWEC 2009 Proceedings online EWEC

Md. Sadak Ali Khan, Syed Ali Sufiyan, Jibu Thomas George, Md. Nizamuddin Ahmed. Analysis of Down-Wind Propeller Vehicle. International Journal of Scientific and Research Publications, 3, 4. (April 2013) ISSN 2250-3153.

The Manim Community Developers. (2021). Manim – Mathematical Animation Framework (Version v0.13.1) [Computer software]. https://www.manim.community/

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Written and Edited by Derek Muller
Animation by Mike Radjabov
Manim equations by Jonny Hyman
Filmed by Emily Zhang and Raquel Nuno
Music from Epidemic Sound https://epidemicsound.com and by Jonny Hyman
Additional video supplied by Getty Images
Produced by Emily Zhang, Petr Lebedev and Derek Muller

Spinning magnets near copper sheets create levitation!
Try Audible free for 30 days: http://bit.ly/AudibleVe
Special thanks to Hyperloop One for showing me around.

Thanks to Patreon supporters:
Nathan Hansen, Donal Botkin, Tony Fadell, Saeed Alghamdi, Zach Mueller, Ron Neal, Perry cl, Bryan Baker
Support Veritasium on Patreon: http://bit.ly/VePatreon

Filmed by Raquel Nuno, Edited by Trevor Carlee

Obviously this "quadcopter" is a demonstration device, showing how moving magnets over a conducting surface can generate levitation. It has not been optimized to minimize losses or be an efficient mode of transport. I still think it's pretty cool. I'm used to seeing light things levitated by induced currents but not a 100+ lb machine.

For more on Hyperloop One: https://hyperloop-one.com/