If you drop a heavy object and a light object simultaneously, which one will reach the ground first? A lot of people will say the heavy object, but what about those who know both will land at the same time? What do they think? Some believe both objects have the same gravitational pull on them and/or both fall to the ground with the same constant speed. Neither of these things is true, however. The force is greater on the heavy object and both objects accelerate at the same rate as they approach the earth, i.e. they both speed up but at the same rate.

Einstein was wrong about black holes, what else? Use code veritasium at the link below to get an exclusive 60% off an annual Incogni plan: https://incogni.com/veritasium

A massive thank you to Prof. Geraint F. Lewis and Prof. Juan Maldacena for their expertise and help with this video.

A huge thank you to those who helped us understand this complicated topic: Dr. Suddhasattwa Brahma, Prof. Carlo Rovelli, Dr. Hal Haggard, Prof. Martin Bojowald, Dr. Francesca Vidotto, Prof. Andrew Hamilton, and Dr. Carl-Fredrik Nyberg Brodda.

A special thanks to Alessandro Roussel from ScienceClic for his spectacular simulations and feedback on the video. Check out his channel here: https://ve42.co/ScienceClic

An excellent book on this topic and an inspiration for this video: Cox, B., & Forshaw, J. (2023). Black holes: the key to understanding the universe.

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Join us on Patreon to watch an exclusive bonus video that expands on the topic of white holes https://ve42.co/PatreonDE

Patrons: Adam Foreman, Anton Ragin, Balkrishna Heroor, Bertrand Serlet, Bill Linder, Blake Byers, Burt Humburg, Chris Harper, 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, Martin, Matthias Wrobel, Max Paladino, Meekay, meg noah, Michael Krugman, 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:
Thorne, K. (1995). Black Holes & Time Warps: Einstein's Outrageous Legacy.
Relativity Playlist by ScienceClic - https://ve42.co/SCPlaylist
Hamilton, A. J. S. (2021). General Relativity, Black Holes, and Cosmology - https://ve42.co/Hamilton2021
Black Hole Events by PBS Space Time - https://youtu.be/vNaEBbFbvcY?l....ist=PLsPUh22kYmNBl4h
Newton’s Letters via The Newton Project - https://ve42.co/NewtonMail
Einstein, A. (1915). Die feldgleichungen der gravitation. - https://ve42.co/Einstein1915
Why Time and Space Swap by ScienceClic - https://youtu.be/GQZ3R81iyE0
Schwarzschild, K. (1916). Über das Gravitationsfeld eines Massenpunktes nach der Einsteinschen Theorie. - https://ve42.co/Schwarzschild1916
Wali, K. C. (1982). Chandrasekhar vs. Eddington—an unanticipated confrontation. - https://ve42.co/Wali1982
How to Build a Black Hole by PBS Space Time - https://www.youtube.com/watch?v=xx4562gesw0
Oppenheimer, J. R., & Volkoff, G. M. (1939). On massive neutron cores. - https://ve42.co/TOVLimit
Oppenheimer, J. R., & Snyder, H. (1939). On continued gravitational contraction. - https://ve42.co/Oppenheimer1939
Schwarzschild Geometry by Andrew Hamilton - https://ve42.co/SchwarzGeom
Why all world maps are wrong by Vox - https://www.youtube.com/watch?v=kIID5FDi2JQ
Hamilton, A. J., & Lisle, J. P. (2008). The river model of black holes. - https://ve42.co/HamiltonLisle2008
Mapping The Multiverse by PBS Space Time - https://www.youtube.com/watch?v=4v9A9hQUcBQ
Rotating black hole via Wikipedia - https://ve42.co/WikiRBH
Wormhole Travel by PBS Space Time - https://www.youtube.com/watch?v=ldVDM-v5uz0
Morris, M. S., & Thorne, K. S. (1988). Wormholes in spacetime and their use for interstellar travel. - https://ve42.co/MorrisThorne1988

Images & Video:
D3 Geo Projection Library by Mike Bostock https://ve42.co/d3geo
Interrupted Maps by Jason Davies https://ve42.co/DaviesMaps
Kazmierczak, J. et al. (2021). NASA’s NICER Tests Matter’s Limits. - https://ve42.co/NasaNICER
Bridgman, T. et al. (2024). M5.1 flare 'Double Whammy', at Active Regions 13559 and 13561. NASA SVS. - https://ve42.co/NasaFlare
Schnittman, J. et al. (2019). Black Hole Accretion Disk Visualization. - https://ve42.co/NasaAccrDisk
Wiessinger, S. et al. (2020). A Decade of Sun. NASA SVS. - https://ve42.co/NasaSunDecade
Skelly, C. et al. (2017). What is a Neutron Star? NASA SVS. - https://ve42.co/NasaNeutron
What would we see if we fell into a black hole by ScienceClic - https://youtu.be/4rTv9wvvat8
Earth texture - https://ve42.co/NASAEarth
First image of Sgr A* - https://ve42.co/EHT1
Image of M87 - https://ve42.co/EHT2
Polarized light image of Sgr A* - https://ve42.co/EHT3

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Directed by Casper Mebius
Written by Casper Mebius, Derek Muller and Will Wood
Edited by Trenton Oliver
Animated by Fabio Albertelli, Ivy Tello, Mike Radjabov, David Szakaly, Jonny Hyman, and Alessandro Roussel
Illustrated by Jakub Misiek
Filmed by Derek Muller
Additional research by Gregor Čavlović
Produced by Casper Mebius, Derek Muller, Will Wood, Giovanna Utichi, Rob Beasley Spence, Gregor Čavlović, and Emily Taylor

Thumbnail contributions by Jakub Misiek, Ren Hurley and Peter Sheppard
Additional video/photos supplied by Getty Images, Storyblocks, and NASA SVS
Music from Epidemic Sound

Go to our sponsor https://betterhelp.com/veritasium to get matched with a professional therapist who will listen and help.

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Huge thanks to the Australian Reptile Park for having us over to film – special thanks to Jake Meney for showing us the spiders and Caitlin Vine for organizing the shoot. https://www.reptilepark.com.au

Huge thanks to Dr Timothy Jackson with his help and answering our questions.

Thanks to Seqirus Australia for providing B-roll footage of the antivenom production process.


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References:

Pineda, S. S., Sollod, B. L., Wilson, D., Darling, A., Sunagar, K., Undheim, E. A., ... & King, G. F. (2014). Diversification of a single ancestral gene into a successful toxin superfamily in highly venomous Australian funnel-web spiders. BMC genomics, 15(1), 1-16 - https://ve42.co/Pineda2014

Isbister, G. K., Gray, M. R., Balit, C. R., Raven, R. J., Stokes, B. J., Porges, K., ... & Fisher, M. M. (2005). Funnel-web spider bite: a systematic review of recorded clinical cases. Medical journal of Australia, 182(8), 407-411 - https://ve42.co/Isbister2005

Herzig, V., Sunagar, K., Wilson, D. T., Pineda, S. S., Israel, M. R., Dutertre, S., ... & Fry, B. G. (2020). Australian funnel-web spiders evolved human-lethal δ-hexatoxins for defense against vertebrate predators. Proceedings of the National Academy of Sciences, 117(40), 24920-24928 - https://ve42.co/Herzig2020

Nicholson, G. M., & Graudins, A. (2002). Spiders of medical importance in the Asia–Pacific: Atracotoxin, latrotoxin and related spider neurotoxins. Clinical and experimental pharmacology and physiology, 29(9), 785-794 - https://ve42.co/Nicholson2002

Fletcher, J. I., Chapman, B. E., Mackay, J. P., Howden, M. E., & King, G. F. (1997). The structure of versutoxin (δ-atracotoxin-Hv1) provides insights into the binding of site 3 neurotoxins to the voltage-gated sodium channel. Structure, 5(11), 1525-1535 - https://ve42.co/Fletcher1997

Australian Reptile Park. (2022). Snake and Spider First Aid - https://ve42.co/ARPFirstAid

The Australian Museum. (20 ). Spider facts - https://ve42.co/SpiderFacts


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Special thanks to our Patreon supporters:
Orlando Bassotto, 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, and Sam Lutfi


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Written by Katie Barnshaw & Derek Muller
Edited by Trenton Oliver
Filmed by Petr Lebedev, Derek Muller and Jason Tran
Animation by Ivy Tello, Jakub Misiek and Fabio Albertelli
Neuron animation by Reciprocal Space – https://www.reciprocal.space
Additional video/photos supplied from Getty Images, Pond5
B-roll supplied by Seqirus Australia
Music from Epidemic Sound
Produced by Derek Muller, Petr Lebedev, Emily Zhang & Katie Barnshaw

The single principle that underpins all of physics. Head to https://brilliant.org/veritasium to start your free 30-day trial and get 20% off an annual premium subscription.

A massive thank you to Prof. Steven Strogatz for his expertise and enthusiasm. As an exclusive bonus for our Patreon members, we've posted a longer interview with Prof. Strogatz over there: https://www.patreon.com/posts/....principle-of-1160428

A huge thank you to Prof. Haithem Taha, Prof. Anthony Bloch, Dr. Carl-Fredrik Nyberg Brodda, Dr. Sarah Millholland, and Dr. Andrew Mitchell for all their help with finding the story and getting it right.

A special thanks to Dr. Aurèle Adam, Ron Haaksman, Marc Serra Peralta, and everyone at the Delft Makerspace for their help with preparing and performing experiments.

00:00 One rule that replaces all of physics
00:51 The problem of fastest descent
05:09 Fermat's principle
07:17 Bernoulli's solution
10:38 Maupertuis' principle
12:28 Maupertuis attacked and ridiculed
14:01 Euler & Lagrange to the rescue
17:22 The general approach to solving these problems
19:32 Writing the principle into its modern form
23:17 Why the principle works
27:08 Another way to do mechanics
30:19 A “spooky” breakthrough

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Join us on Patreon for early access videos and exclusive bonus content https://ve42.co/PatreonDE

Patrons: Adam Foreman, Anton Ragin, Balkrishna Heroor, Bertrand Serlet, Bill Linder, Blake Byers, Burt Humburg, Chris Harper, 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, Martin, Matthias Wrobel, Max Paladino, Meekay, meg noah, Michael Krugman, 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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Key references:

A fantastic book on the history of the Principle of Least Action: Rojo, A. and Bloch, A. The
Principle of Least Action: History and Physics. - https://ve42.co/Bloch2018
Coopersmith, J. (2017). The lazy universe: an introduction to the principle of least action. Oxford University Press. - https://ve42.co/LazyU
3Blue1Brown. The Brachistochrone, with Steven Strogatz via Youtube - https://ve42.co/Brach3B1B
Vsauce. The Brachistochrone via Youtube - https://ve42.co/BrachV
PBS Space Time. Is ACTION The Most Fundamental Property in Physics? via Youtube - https://ve42.co/PBSAction

Full list of references: https://ve42.co/LeastActionRefs

Images & Video:
Voltaire. (1753). Diatribe du Docteur Akakia. - https://ve42.co/DiatribeAkakia
Philosophical Transactions cover. via Wikimedia Commons - https://ve42.co/PhilTransImage
Kids Fun Science. (Jun 28, 2017). Refraction of Light with a arrow experiment via Youtube - https://ve42.co/RefractionFunSci
Physics with Simon Poliakoff. Refraction demonstration with water and laser via Youtube - https://ve42.co/SimonPoliakoff
Mercury Transit Across Sun. via Nasa.gov - https://ve42.co/MercTransit


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Directed by Casper Mebius
Written by Casper Mebius and Derek Muller
Edited by Trenton Oliver
Animated by Fabio Albertelli, Ivy Tello, Mike Radjabov, Gregor Čavlović, Emma Wright, James Finnemore and David Szakaly
Illustrated by Jakub Misiek, Emma Wright, and Maria Gusakovich
Filmed by Derek Muller and Casper Mebius
Additional research by Gabe Strong, Gregor Čavlović, and Geeta Thakur
Produced by Casper Mebius, Derek Muller, Rob Beasley Spence, Gabe Strong, Gregor Čavlović, and Tori Brittain
Thumbnail contributions by Jakub Misiek, Ren Hurley and Peter Sheppard
Additional video/photos supplied by Getty Images, Storyblocks, and NASA SVS
Music from Epidemic Sound

Bowling has been reinvented many times over the past seven thousand years but especially in the last 30. This is the fascinating physics of balls, oil, lane and pins. A portion of this video was sponsored by Salesforce. Go to https://salesforce.com/veritasium to learn more.

Huge thanks to Steve Kloempken and all of Storm Bowling for letting us visit and get a glimpse into the crazy world of bowling.
Huge thanks to legends Chris Barnes and Pete Weber for taking the time to bowl with us.
Huge thanks to Creative Electron for their help with getting the bowling balls X-rayed. Check out their work here: https://creativeelectron.com/
Thanks to Ron Hatfield and James Freeman for their help with research. Check out their great book, Bowling Beyond the Basics: https://ve42.co/HatfieldFreeman
Thanks to the United States Bowling Congress (USBC) and Professional Bowlers Association (PBA) for their help with accessing archival data and footage.
Special thanks to Rod Cross for physics consultation.
Thanks to Bill Guszczo for giving us the idea to make this video in the first place.

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References:
Freeman, James, and Ron Hatfield. Bowling beyond the Basics: What's Really Happening on the Lanes, and What You Can Do about It. BowlSmart, 2018. -- https://ve42.co/HatfieldFreeman
N. Stremmel, P. Ridenour and S. Sterbenz. “Identifying the Critical Factors That Contribute to Bowling Ball Motion on a Bowling Lane.” United States Bowling Congress, 2008. -- https://ve42.co/BallMotionASQ
USBC Equipment Specifications and Certification Team. “Ball Motion Study: Phase I and II Final Report.” United States Bowling Congress, 2008. -- https://ve42.co/USBCBallMotion
Brettingen, Patrick, and Nicki Mours. “USBC static weight limits remain relevant.” United States Bowling Congress, 2011. -- https://ve42.co/USBCStaticWeight
Article on lane oil origins -- https://ve42.co/OilOrigins
Luna, Richard. “Bruce Pluckhahn says there's a little bit of bowling…” United Press International Archives, 1984. -- https://ve42.co/BowlingHistory
Johnson, Brody D. “The Physics of Bowling: How good bowlers stay off the straight and narrow.” St. Louis University. -- https://ve42.co/JohnsonPhysicsPpt
Talamo, Jim. “The Physics of Bowling Balls.” -- https://ve42.co/TalamoPhysicsPpt
Thompson, Ted. “Breakdown and Carrydown - Then and Now.” Kegel. 2012. -- https://ve42.co/ThompsonKegel
Frohlich, Cliff. “What Makes Bowling Balls Hook?” American Journal of Physics, vol. 72, no. 9, 2004, pp. 1170–1177., https://doi.org/10.1119/1.1767099. -- https://ve42.co/FrohlichHook
Article on bowling’s ranking in participatory sports -- https://ve42.co/BowlingRank
Speranza, Dan, and Dave Nestor. “Initial Oil Absorption Results.” United States Bowling Congress, 2016. -- https://ve42.co/USBCOilAbsorption
D. Benner, N. Mours, and P. Ridenour. “Pin Carry Study: Bowl Expo 2009.” United States Bowling Congress, 2009. -- https://ve42.co/USBCPinCarry
Hopkins, D. C., and J. D. Patterson. “Bowling Frames: Paths of a Bowling Ball.” American Journal of Physics, vol. 45, no. 3, 1977, pp. 263–266., https://doi.org/10.1119/1.11005. -- https://ve42.co/HopkinsPath
Normani, Franco. “The Physics of Bowling.” Real World Physics Problems. -- https://ve42.co/NormaniPhysics
Horaczek, Stan. “The insides of pro bowling balls will make your head spin.” Popular Science, 2020. -- https://ve42.co/HoraczekSpin
House shot oil pattern -- https://ve42.co/HouseOil. Licensed under Creative Commons: By Attribution 4.0.

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Special thanks to Patreon supporters: Andrew, Diffbot, Micah Mangione, MJP, Gnare, Nick DiCandilo, Dave Kircher, Edward Larsen, Burt Humburg, Blake Byers, Dumky, Evgeny Skvortsov, Meekay, Bill Linder, Paul Peijzel, Mac Malkawi, Michael Schneider, Big Badaboom, Ludovic Robillard, Jim buckmaster, fanime96, Juan Benet, Ruslan Khroma, Robert Blum, Richard Sundvall, Lee Redden, Vincent, Marinus Kuivenhoven, Alfred Wallace, Clayton Greenwell, Michael Krugman, Cy 'kkm' K'Nelson, Sam Lutfi, Ron Neal

Written by Derek Muller and Emily Zhang
Animations by Mike Radjabov and Ivy Tello
Filmed by Derek Muller, Trenton Oliver, and Emily Zhang
Edited by Trenton Oliver
SFX by Shaun Clifford
Additional video supplied by Getty Images
Music from Epidemic Sounds
Produced by Derek Muller, Petr Lebedev, and Emily Zhang

The Salton Sea is the largest body of water in California, home to the second most diverse group of birds in America and it exists by accident.
Another great video on the Salton Sea: https://youtu.be/otIU6Py4K_A
I used archive from this video.

Music by Kevin MacLeod, www.incompetech.com ‘Mirage’, ‘Hyperfun’, ‘Marty Gots a Plan’, ‘Past the Edge’

Tiny particles from distant galaxies have caused plane accidents, election interference and game glitches. This video is sponsored by Brilliant. The first 200 people to sign up via https://brilliant.org/veritasium get 20% off a yearly subscription.

This video was inspired by the RadioLab Podcast "Bit Flip" https://ve42.co/BF -- they're brilliant science storytellers.

A Huge thanks to Dr Leif Scheick, Calla Cofield and the JPL Media Relations Team.

Thanks to Col Chris Hadfield. Check out his book: https://chrishadfield.ca/books/

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References:
J. F. Ziegler, "Terrestrial cosmic rays," in IBM Journal of Research and Development, vol. 40, no. 1, pp. 19-39, Jan. 1996, doi: 10.1147/rd.401.0019. -- https://ve42.co/Ziegler1996

D. Binder, E. C. Smith and A. B. Holman, "Satellite Anomalies from Galactic Cosmic Rays," in IEEE Transactions on Nuclear Science, vol. 22, no. 6, pp. 2675-2680, Dec. 1975, doi: 10.1109/TNS.1975.4328188 https://ve42.co/Binder1975

Ziegler, J. F., & Lanford, W. A. (1979). Effect of cosmic rays on computer memories. Science, 206(4420), 776-788 https://ve42.co/Ziegler1979

Drury, L. O. C. (2012). Origin of cosmic rays. Astroparticle Physics, 39, 52-60. https://ve42.co/Drury2012

Hess, V. (2018). On the observations of the penetrating radiation during seven balloon flights. arXiv preprint arXiv:1808.02927. --https://ve42.co/Hess2018

Carlson, P., & De Angelis, A. (2011). Nationalism and internationalism in science: the case of the discovery of cosmic rays. The European Physical Journal H, 35(4), 309-329. -- https://ve42.co/Carlson2011

Höeffgen, S. K., Metzger, S., & Steffens, M. (2020). Investigating the effects of cosmic rays on space electronics. Frontiers in Physics, 8, 318. -- https://ve42.co/Hoeffgen2020

Edmonds, L. D., Barnes, C. E., & Scheick, L. Z. (2000). An introduction to space radiation effects on microelectronics. Jet Propulsion Laboratory, National Aeronautics and Space Administration. -- https://ve42.co/Edmonds2000

NASA Mars 2020 website covering the specifications of the Perseverance Rover https://ve42.co/RoverBrains

Australian Government Australian Transport Safety Bureau report on QF72 -- https://ve42.co/ASTBQantas

Australian Government Australian Transport Safety Bureau summary on QF72 --https://ve42.co/ASTBQantas2

Great Blog post about QF72 -- https://ve42.co/DempseyQantas

Michael Barr's report on the Toyota acceleration issue --https://ve42.co/Barr2015

NASA's Report on Toyota -- https://ve42.co/NASAToyota

T. C. May and M. H. Woods, "A New Physical Mechanism for Soft Errors in Dynamic Memories," 16th International Reliability Physics Symposium, 1978, pp. 33-40, doi: 10.1109/IRPS.1978.362815. --https://ve42.co/May1978

P. M. O'Neill and G. D. Badhwar, "Single event upsets for Space Shuttle flights of new general purpose computer memory devices," in IEEE Transactions on Nuclear Science, vol. 41, no. 5, pp. 1755-1764, Oct. 1994, doi: 10.1109/23.317386. -- https://ve42.co/ONeill1994

Wikipedia about radiation hardening -- https://ve42.co/RadHardening

Toward Monitoring Fault-Tolerant Embedded
Systems (Extended Abstract) -- https://ve42.co/Goodloe2009

Article about speed run -- https://ve42.co/BurttSpeedrun

Article about speed run -- https://ve42.co/BountySpeedrun

Article about redundant systems in spaceflight -- https://ve42.co/NASAComputers

Article about the PowerPC750 -- https://ve42.co/Wener-FlignerNASA

Fuglesang C, Narici L, Picozza P, Sannita WG. Phosphenes in low earth orbit: survey responses from 59 astronauts. Aviat Space Environ Med. 2006 Apr;77(4):449-52. PMID: 16676658. -- https://ve42.co/Fuglesang2006

Good article about Cosmic Rays causing flashes -- https://ve42.co/AtkinsonEye

Good article about radiation resistance -- https://ve42.co/RoverResistance

Special thanks to Patreon supporters: Paul Peijzel, Juan Benet, Ruslan Khroma, Richard Sundvall, Lee Redden, Sam Lutfi, MJP, Gnare, Nick DiCandilo, Dave Kircher, Edward Larsen, Burt Humburg, Blake Byers, Dumky, Mike Tung, Evgeny Skvortsov, Meekay, Ismail Öncü Usta, Paul Peijzel, Crated Comments, Anna, Mac Malkawi, Michael Schneider, Oleksii Leonov, Jim Osmun, Tyson McDowell, Ludovic Robillard, Jim buckmaster, fanime96, Juan Benet, Ruslan Khroma, Robert Blum, Richard Sundvall, Lee Redden, Vincent, Marinus Kuivenhoven, Alfred Wallace, Arjun Chakroborty, Joar Wandborg, Clayton Greenwell, Pindex, Michael Krugman, Cy 'kkm' K'Nelson, Sam Lutfi, Ron Neal

Written by Derek Muller and Petr Lebedev
Animation by Ivy Tello, Mike Radjabov, Fabio Albertelli, Jakub Misiek and Charlie Davies
SFX by Shaun Clifford
Filmed by Derek Muller, Raquel Nuno, and Emily Zhang
Edited by Derek Muller and Petr Lebedev
SFX by Shaun Clifford
Additional video supplied by Getty Images
Rover Footage From NASA/JPL-Caltech
QF72 footage from the Smithsonian channel https://youtu.be/H3q5S9PCoJA
SM64 footage from https://ve42.co/pannenkoek2012
Music from Epidemic Sound
Produced by Derek Muller, Petr Lebedev and Emily Zhang

This deceptively simple math problem has stumped mathematicians for almost 300 years! 👉 Head to https://hensonshaving.com/veritasium and enter code 'Veritasium' for 100 free blades with the purchase of a razor. Make sure to add both the razor and the blades to your cart for the code to take effect.

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

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A huge thank you to Steven Strogatz, Alex Kontorovich, Harald Helfgott, Senia Sheydvasser, Jared Duker Lichtman, Roger Heath-Brown, Kevin Ford, Carl-Fredrik Nyberg Brodda, Kaneenika Sinha & Shehzad Hathi for their invaluable expertise and contributions to this video.

Look out for the upcoming @fern-tv video on the tragic life of Srinivasa Ramanujan! A huge thank you to Ruben Katschko, Mathias Hawk, Chris Varga, Elmer and David from fern for working with us!

The full interview with Steven Strogatz is out now, exclusive to Patreon! - https://www.patreon.com/c/veritasium

▀▀▀
0:00 What is Goldbach’s Conjecture?
4:33 Goldbach and Euler
7:03 The Prime Number Theorem
11:16 The Genius of Ramanujan
14:57 The Circle Method
27:31 Proving the Weak Goldbach Conjecture
32:40 Math vs Mao
36:06 Back to Chen Jingrun
37:15 How you can prove the Strong Goldbach Conjecture

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References:
References can be found here - https://ve42.co/GoldbachRefs

Images & Video:
Image and video references can be found here - https://ve42.co/GoldbachVisuals

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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, Dave Kircher, David Johnston, David Tseng, Evgeny Skvortsov, Garrett Mueller, Gnare, gpoly, iRick, Jeromy Johnson, Jon Jamison, JT, Juan Benet, Keith England, KeyWestr, Kyi, Lee Redden, Marinus Kuivenhoven, Matthias Wrobel, Meekay, meg noah, Michael Krugman, Orlando Bassotto, Paul Peijzel, Richard Sundvall, Robert Oliveira, Sam Lutfi, Tj Steyn, TTST, Ubiquity Ventures, wolfee

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Writers: Casper Mebius & Derek Muller
Additional Writers: Darius Garewal, Callum Cuttle & Aakasha Bagga
Producer & Director: Casper Mebius
Editors: Jack Saxon & Peter Nelson
Camera Operators: Casper Mebius & Derek Muller
Animators: Fabio Albertelli, Emma Wright, Ivy Tello, Allama Nandii, Emma Foster, Mike Radjabov & Andrew Neet
Illustrators: Maria Gusakovich, Jakub Misiek & Caine Esperanza
Assistant Editor: James Stuart
Researchers: Darius Garewal, Geeta Thakur & Gabe Strong
Thumbnail Designers: Ren Hurley & Ben Powell
Production Team: Rob Beasley Spence, Tori Brittain, Casper Mebius & Gregor Čavlović
Advice & Feedback: Gregor Čavlović
Executive Producers: Derek Muller & Casper Mebius

Additional video/photos supplied by Getty Images, Pond5.
Music from Epidemic Sound

The Fast Fourier Transform is used everywhere but it has a fascinating origin story that could have ended the nuclear arms race. This video is sponsored by 80,000 Hours. Head to http://80000hours.org/veritasium to sign up for their newsletter and get sent a free copy of their in-depth career guide.

A huge thank you to Dr. Richard Garwin for taking the time to speak with us.
Thanks to Dr. Steve Brunton of the University of Washington for his help with understanding the Fast Fourier Transform.

Thanks to Dr. Cliff Thurber of the University of Wisconsin-Madison, Dr. Paul Richards of Columbia University, and Dr. Steven Gibbons of the Norwegian Geotechnical Institute for their expertise.

Thanks to Grant Sanderson of 3Blue1Brown for his helpful feedback on the script. His great video on the Fourier Transform is here - https://youtu.be/spUNpyF58BY

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References:

Kristensen, H.M., Korda, M. (2022). Status of World Nuclear Forces. Federation of American Scientists (FAS). https://ve42.co/Stockpile2022

Barth, K. H. (1998). Science and politics in early nuclear test ban negotiations. Physics Today, 51(3), 34-39. - https://ve42.co/Barth1998

Schmalberger, T. (1991). In pursuit of a nuclear test ban treaty - https://ve42.co/Schmalberger1991

Bowers, D., & Selby, N. D. (2009). Forensic seismology and the comprehensive nuclear-test-ban treaty. Annual Review of Earth and Planetary Sciences, 37, 209-236 - https://ve42.co/Bowers2009

Incorporated Research Institutions for Seismology (IRIS). (2022). How Often Do Earthquakes Occur? https://ve42.co/IRIS2022

Kimball, D. (2022). The Nuclear Testing Tally. Arms Control Association. https://ve42.co/TestTally2022

Kværna, T., & Ringdal, F. (2013). Detection capability of the seismic network of the International Monitoring System for the Comprehensive Nuclear Test Ban Treaty. Bulletin of the Seismological Society of America, 103(2A), 759-772 - https://ve42.co/Kvrna2013

Sykes, L. R., & Evernden, J. F. (1982). The verification of a comprehensive nuclear test ban. Scientific American, 247(4), 47-55 - https://ve42.co/Sykes1982

Peterson, J., & Hutt, C. R. (2014). World-wide standardized seismograph network: a data users guide (p. 82). US Department of the Interior, US Geological Survey. - https://ve42.co/Peterson2014

Richards, P. G., & Kim, W. Y. (2009). Monitoring for nuclear explosions. Scientific American, 300(3), 70-77 - https://ve42.co/Richards2009

Jacobsen, L. L., Fedorova, I., & Lajus, J. (2021). The seismograph as a diplomatic object: The Soviet–American exchange of instruments, 1958–1964. Centaurus, 63(2), 277-295 - https://ve42.co/Jacobsen2021

Schwartz S. I. (1998). The Hidden Costs Of Our Nuclear Arsenal: Overview Of Project Findings. The Brookings Institution - https://ve42.co/Schwartz1998

Ricón, J.L. (2016). The Soviet Union: Military Spending. Nintil - https://ve42.co/Nintil2016

Heideman, M. T., Johnson, D. H., & Burrus, C. S. (1985). Gauss and the history of the fast Fourier transform. Archive for history of exact sciences, 265-277 - https://ve42.co/Heideman1985

Ford, D. (2004). Richard Garwin - Session IV. American Institute of Physics (AIP). - https://ve42.co/Ford2004

Aaserud, F. (1986). Richard Garwin - Session I. American Institute of Physics (AIP). - https://ve42.co/Aaserud1986

Goldstein, A. (1997). James W. Cooley, an oral history. IEEE History Center, Piscataway, NJ, USA - https://ve42.co/Goldstein1997

Cooley, J., Garwin, R., Rader, C., Bogert, B., & Stockham, T. (1969). The 1968 Arden House workshop on fast Fourier transform processing. IEEE Transactions on Audio and Electroacoustics, 17(2), 66-76 - https://ve42.co/Cooley1969


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Special thanks to Patreon supporters:
Louis Lebbos, Elliot MIller, RayJ Johnson, Brian Busbee, Jerome Barakos M.D., Amadeo Bee, TTST, Balkrishna Heroor, Chris LaClair, John H. Austin, Jr., OnlineBookClub.org, Matthew Gonzalez, Eric Sexton, John Kiehl, Diffbot, Gnare, Dave Kircher, Burt Humburg, Blake Byers, Dumky, Evgeny Skvortsov, Meekay, Bill Linder, Paul Peijzel, Josh Hibschman, Mac Malkawi, Mike Schneider, John Bauer, jim buckmaster, Juan Benet, Sunil Nagaraj, Richard Sundvall, Lee Redden, Stephen Wilcox, Marinus Kuivenhoven, Michael Krugman, Cy 'kkm' K'Nelson, Sam Lutfi, Ron Neal

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Written by Derek Muller & Felicity Nelson
Filmed by Derek Muller & Raquel Nuno
Animation by Ivy Tello, Jakub Misiek, Alex Drakoulis, and Fabio Albertelli
Edited by Albert Leung & Derek Muller
Research Assistant: Katie Barnshaw
Additional video/photos supplied by Pond5 and Getty Images
Music from Epidemic Sound
Produced by Derek Muller, Petr Lebedev, and Emily Zhang

The surprising science of escalators. Sponsored by Brilliant - check out https://brilliant.org/veritasium to start learning for free.
Plus, our viewers get 20% off an annual Premium subscription for unlimited daily access to all Brilliant courses.

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


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A massive thank you to Emily Zhang for suggesting this idea and helping shape it.

A huge thanks to the team at OTIS, especially Ed Jacovino, Gregory Sefcik and Dirk Winkelhake, for their time and expertise.

Thank you also to Professor Gero Gschwendtner, Professor Michael Fu, and Dr. Peter Kauffmann for all their help on the project.


▀▀▀
0:00 When escalators go wrong
2:43 The first escalator
5:01 How does an escalator work?
8:35 Why do escalators have grooves?
10:05 Why do escalators have brushes?
10:21 The hand rail moves faster than the steps
12:05 You generate electricity on escalators
14:09 How does an escalator break?
18:47 How safe are escalators really?


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References: https://ve42.co/EscalatorRefs
Images & Video: https://ve42.co/EscalatorImgRefs


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Special thanks to our Patreon supporters:
Alex Porter, Alexander Tamas, Anton Ragin, Anupam Banerjee, Gnare, Ibby Hadeed, Jon Jamison, Juan Benet, Lee Redden, Meekay, Orlando Bassotto, Paul Peijzel, Richard Sundvall, Sam Lutfi, Ubiquity Ventures, Adam Foreman, Albert Wenger, armedtoe, Balkrishna Heroor, Bertrand Serlet, Blake Byers, Bruce, Dave Kircher, David Johnston, David Tseng, Evgeny Skvortsov, Garrett Mueller, gpoly, Jeromy Johnson, JT, Justin Waters, KeyWestr, Kyi, Marinus Kuivenhoven, Matthias Wrobel, meg noah, Michael Bush, Michael Krugman, Robert Oliveira, Tj Steyn, wolfee.

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Writers - Darius Garewal, Casper Mebius, Emily Zhang & Derek Muller
Presenters - Derek Muller & Latif Nasser
Producer & Director - Darius Garewal
Editor - Spencer Wright
Camera Operators - Derek Muller, Darius Garewal & Gregory Sefcik
Animators - Mike Radjabov, Fabio Albertelli, Saif Javed, Andrew Neet & Rokas Viksraitis
Illustrators - Jakub Misiek & Nataly Zhuk
Additional Editors - James Stuart, James Horsley, Peter Nelson & Kyle Rossiter
Researchers - HyoJeong Choi, Callum Cuttle & Gabe Strong
Thumbnail Designers - Ren Hurley, Ben Powell & Abdallah Rabah
Production Team - Nicola Griffiths, Josh Pitt, Rob Beasley Spence & Casper Mebius
Executive Producers - Casper Mebius & Derek Muller

Additional video/photos supplied by Getty Images, Pond5 & StoryBlocks
Music from Epidemic Sound

How an unlikely physics paradox controls these counterintuitive structures.

The world’s first look inside a thermite reaction. Use code veritasium at https://incogni.com/veritasium to get an exclusive 60% off an annual Incogni plan.

A massive thank you to everyone at Goldschmidt for making this possible. With special thanks to Dr. Axel Hoeschen, Christof Gassmann and Claudia Koch.

00:00 What is thermite?
00:51 Hans Goldschmidt and the first thermite reaction
05:55 The reaction as it’s never been seen before
14:57 How thermite welding works
17:43 I destroyed a laptop!
26:44 How thermite is made
31:11 Blow-torching thermite to show how reactive it is

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

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References:

Archives from Goldschmidt
Thermite via Wikipedia - https://ve42.co/WikiThermite
From the past to the present. via goldschmidt.com - https://ve42.co/Past2Present
Hans Goldschmidt via Wikipedia - https://ve42.co/HansGWiki
Goldschmidt, H. (1914). Gesammelte Veröffentlichungen (1st Ed.). Springer-Verlag - https://ve42.co/HGoldschmit1914
Menzies, J. (2015, January 8). Mechanic's Toolbox: Thermite Welding. SFMTA. - https://ve42.co/ThermiteWelding
Kirshenbaum, A. D., & Cahill, J. A. (1960). The density of liquid aluminium oxide. Journal of Inorganic and Nuclear Chemistry - https://ve42.co/CahillA1960
Reichstag fire via Wikipedia - https://ve42.co/ReichstagFireWiki

Images & Video:

Karl Goldschmidt - https://ve42.co/KGoldschmidt
Goldschmidt Chemical Factory - https://ve42.co/GSFabrik
Henry Treffry Dunn Rossetti and Dunton at 16 Cheyne Walk - https://ve42.co/Treffry
The Green Gown - https://ve42.co/GreenGown
Arsenic Green Dress - https://ve42.co/ArsenicGreenDress
Kersting, Die Stickerin - https://ve42.co/Fassung
Too Early Tissot Detail - https://ve42.co/Tissot
Death Skull - https://ve42.co/Skull
British uniforms - https://ve42.co/BritishUniforms
Thermit in Practice - https://ve42.co/SKallee
Thermite Ship Shaft Welding 1 - https://ve42.co/ShipShaft1
Thermite Ship Shaft Welding 2 - https://ve42.co/ShipShaft2
Using Incendiary Grenade to Destroy German Antitank Gun by OkraJoe - https://youtu.be/RTSiq5QYHGo?si=Va_6dPimFuaQfFp5
Reichstagsbrand - https://ve42.co/RTBrand
Ruins of the Reichstagsbrand - https://ve42.co/RTBrand2
The Thermite Kettle by colinfurze - https://youtu.be/mg3bFxdAZsY?si=BmBIYPUlP1Wfpuoj


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Special thanks to our Patreon supporters:

Albert Wenger, Anton Ragin, Ayush Agrawal, Balkrishna Heroor, Bertrand Serlet, Bill Linder, Blake Byers, Bruce, Dave Kircher, David Johnston, Evgeny Skvortsov, Garrett Mueller, Gnare, I. H., Jack Cuprill, John H. Austin, Jr., Juan Benet, KeyWestr, Kirill Shore, Kyi, Lee Redden, Marinus Kuivenhoven, Matthias Wrobel, Meekay, Michael Krugman, Orlando Bassotto, Paul Peijzel, Reed Spilmann, Richard Sundvall, Sam Lutfi, TTST, Tj Steyn, Ubiquity Ventures, gpoly, john kiehl, meg noah, wolfee

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Directed by Derek Muller
Written by Derek Muller
Edited by Trenton Oliver
Animated by Fabio Albertelli, Rokas Vikšraitis and Mike Radjabov
Illustrations by Jakub Misiek
Filmed by Derek Muller, David Bochmann, Casper Mebius, Luise Dietert, Henning Fischer and Harald Schweiger
Additional Research by Gregor Čavlović and Gabriel Strong
Produced by Gregor Čavlović, Derek Muller, Casper Mebius, Rob Beasley Spence, Emily Lazard and Tori Brittain

Thumbnail contributions by Peter Sheppard, Ren Hurley and Casper Mebius
Additional video/photos supplied by Getty Images and Story Blocks
Music from Epidemic Sound

I took a boat through 96 million black plastic balls on the Los Angeles reservoir to find out why they're there. The first time I heard about shade balls the claim was they reduce evaporation. But it turns out this isn't the reason they were introduced.

Huge thanks to LADWP for arranging this special tour for me. Next time let's put the GoPro on the submersible!

The balls are made of high density polyethylene (HDPE) which is less dense than water so they float on the surface of the reservoir even if they break apart. They are 10cm (4 inches) in diameter and contain about 210ml of water. So the main reason they are on the reservoir is to block sunlight from entering the water and triggering a chemical reaction that turns harmless bromide into carcinogenic bromate. This effect occurs with prolonged exposure to bromate so regulators insist that levels be kept below 10 microgram per liter on average over a 12 month period.

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

Thanks to:
Las Virgenes Reservoir for footage of initial shade ball dump
Euro-Matic for bird into jet-engine footage

Researched and Produced by Casey Rentz

Animations by Maria Raykova

Music from http://epidemicsound.com "Colorful Animation 4" "Seaweed"

And from Kevin MacLeod "Marty Gots a Plan"

This is an educational video about the science of water quality.

How jumping spiders reveal an entire secret world of colors. Let BetterHelp connect you to a therapist who can support you - all from the comfort of your own home. Visit https://betterhelp.com/veritasium and enjoy a special discount on your first month.

A massive thank you to everyone at Day’s Edge Productions for making this documentary happen. Check them out at https://daysedge.com/.

You can watch the full-length documentary “Spider Vision: Decoding Color” on Curiosity Stream - coming soon.

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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, Chris Harper, 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, Martin, Matthias Wrobel, Max Paladino, Meekay, meg noah, Michael Krugman, 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

Production by Day's Edge fully funded by National Science Foundation (Grant #IOS 1831767)

Featuring: Dr. Nathan Morehouse (University of Cincinnati); Olivia Harris (University of Cincinnati), Dr. Megan Porter (University of Hawaii); Dr. Lisa Taylor (University of Florida); Dr. Wayne Maddison (University of British Columbia); and Dr. Emma Alexander (Northwestern University)

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Directed by Neil Losin
Written by Neil Losin
Edited by Neil Losin, Andy Laub, and Alan Saunders
Animated by Root House Studio and David Hutchinson
Filmed by Neil Losin, Nate Dappen, Alex Wiles, Andy Laub, and Barend van der Watt
Produced by Day’s Edge Productions

Repurposed for YouTube by Derek Muller, Casper Mebius, Petr Lebedev, Peter Nelson, Trenton Oliver, Emily Zhang, Giovanna Utichi, Rob Beasley Spence, Emily Taylor, and Gregor Čavlović

Thumbnail contributions by Ren Hurley and Peter Sheppard

Video/photos supplied by Day’s Edge Productions and Storyblocks
Music by Adrian Younge, PBS, Epidemic Sound, and Jonny Hyman

Check out 2Veritasium! https://ve42.co/2Ve
MinutePhysics has a great video on Milkman, vomiting levitator: http://dft.ba/-vomphysics
Jetpacking was awesome fun! Despite the fat lip I had a great time. I think knowing a bit about physics actually helps fly the jetpack. It works on the same principle as a rocket (Newton's 3rd law) but unlike the shuttle, you don't carry your own propellant with you. Instead, water is pumped out of the lake by the jetski at up to 60 litres a second. It is then fired out of the nozzles at around 15 m/s creating 1800 N of force, the equivalent of about 150 fire extinguishers. On me this can produce acceleration of about 1.5g's.

Music by Kevin McLeod (http://incompetech.com) Silly Fun, Also Sprach Zarathustra
Supported by Science Alert: http://on.fb.me/14ehuxA
Slow motion filming by Questacon: http://bit.ly/ZoWFGR

How much information is there in Spanish vs English, you vs the world? Check out Audible: http://bit.ly/AudibleVe
Huge thanks to all the amazing people who made this possible:
Christina Ochoa - Spanish https://twitter.com/christina_ochoa
Vanessa Hill - Filming https://www.youtube.com/braincraftvideo
Henry Reich - Filming, cameo http://youtube.com/minutephysics
Cara Santa Maria - Set design http://carasantamaria.com
Michael Stevens - cameo http://youtube.com/vsauce
Crystal Dilworth - consultation https://twitter.com/PolycrystalhD

Thanks also to MinutePhysics for wardrobe and lending the use of the amazing "Things to do when it's really cold outside" video: https://www.youtube.com/watch?v=j3Gs6tyiNX4

More on this theme to come in the main collaboration with Vsauce.

The world's strongest magnet is a million times stronger than Earth's magnetic field. Learn more about sustainability and Google’s efforts at sustainability.google. Part of this video was sponsored by Google.

Trends insights for the past year are based on Google Trends data from 2/10/2022 - 2/10/2023, U.S.

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Thanks to the entire NHMFL team - especially Tim, Stephen, Caroline, Kristin, Sam, Lance, and everyone who helped with the demos - for the great visit.
The NHMFL is funded by the National Science Foundation and the State of Florida.

Special thanks to Henry from Minutephysics for lending his magnet animations from our magnet collaboration: https://youtu.be/hFAOXdXZ5TM

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References:
Liu, Y., Zhu, D. M., Strayer, D. M., & Israelsson, U. E. (2010). Magnetic levitation of large water droplets and mice. Advances in Space Research, 45(1), 208-213.

Simon, M. D., & Geim, A. K. (2000). Diamagnetic levitation: Flying frogs and floating magnets. Journal of applied physics, 87(9), 6200-6204.

Berry, M. V., & Geim, A. K. (1997). Of flying frogs and levitrons. European Journal of Physics, 18(4), 307.

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Special thanks to our Patreon supporters:
Tj Steyn, Meg Noah, Bernard McGee, James Sanger, Elliot Miller, Jerome Barakos M.D., Amadeo Bee, TTST, Balkrishna Heroor, Chris LaClair, John H. Austin Jr., Eric Sexton, John Kiehl, Anton Ragin, Diffbot, Gnare, Dave Kircher, Burt Humburg, Blake Byers, Evgeny Skvortsov, Meekay, Bill Linder, Paul Peijzel, Josh Hibschman, Mac Malkawi, Juan Benet, Sunil Nagaraj, Richard Sundvall, Lee Redden, Stephen Wilcox, Marinus Kuivenhoven, Michael Krugman, Cy 'kkm' K'Nelson, Sam Lutfi

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Written by Derek Muller
Edited and Motion Graphics by Trenton Oliver
Coordinated by Emily Zhang and Derek Muller
Filmed by Derek Muller, Trenton Oliver, Raquel Nuno and Emily Zhang
Additional video/photos supplied by Pond5 & Getty Images
Music from Epidemic Sound
Thumbnail by Ignat Berbeci
Produced by Derek Muller, Petr Lebedev, and Emily Zhang

Aerogel has extraordinary properties but it can be tough to work with. This video looks at modifying aerogels to take advantage of their unique characteristics.
Subscribe to Veritasium: https://ve42.co/sub

Huge thanks to Dr. Stephen Steiner and the crew at Aerogel Technologies. To find out more or buy your own aerogel sample, check out: http://www.aerogeltechnologies.com/

Thanks to Dr. Steven Jones and Dr. Mihail Petkov at NASA's Jet Propulsion Laboratory

And thanks to FLIR for loaning us the awesome high definition thermal camera. The footage is amazing! https://www.flir.com

Aerogel’s extraordinary properties are due in large part to its structure. Aerogel is a solid but on the nanoscale it has a mesh or sponge-like structure. The struts of this structure are nanoscale, as are the pores at around 20nm across. This makes silica aerogel incredibly light (it was once the lightest solid but has now been superseded by graphene aerogel), transparent and adsorbent.

An ice-cube sized piece of aerogel has an internal surface area roughly equal to half a football field. Aerogel is used in high end museum cases to regulate humidity. Plus it helps maintain the vacuum on the Mars Insight seismometers - it adsorbs moisture and other outgassed volatiles that come from the spacecraft itself. Proposed uses include as a physical insecticide by ‘drying out insects’ reducing the need for chemical and toxic pesticides.

Special thanks to all my Patreon supporters especially those who contributed feedback to an earlier draft of this video:
a human, Albert Jachowicz-Brzeziński, Alfred Wallace, Arjun Chakroborty, Brent Stewart, Chris Vargas, Chuck Lauer Vose, Clip Tree, Coale Shifflett, Colin Bellmore, DALE HORNE, Eric Velazquez, Fedor Indutny, Fran Rodriguez, James Wong, Jasper Xin, Joar Wandborg, Johnny, Jorge Angel Sandoval, June Kang, Kevin Beavers, Kishore Tipirneni, Levan Ferr, Listen Money Matters, Manuel Zürcher, Mark Bevilacqua, Mathias Göransson, Michael Bradley Wirz, Michael Krugman, Mohammed Al Sahaf, Nicholas Hastings, OddJosh, Patrick Čalija, Peter Tajti, Philipp Volgger, Roberto Rezende, Robin DeBank, Ron Neal, Stan Presolski, Swante Scholz, Tiago Bruno, Tige Thorman, Warrior8252

Filmed by Paul Gramaglia

Thumbnail by Ignat Berbeci

Animations by Catherine Chooljian

Music from https://epidemicsound.com “Tonic Zone” “Betelgeuse” “Insidious Mice” “Seaweed” “It’s not that serious” “Platin00m - Sum It”

This is an educational, scientific video.

IQ is supposed to measure intelligence, but does it? 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.

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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A huge thank you to Emeritus Professor Cecil R. Reynolds and Dr. Stuart J. Ritchie for their expertise and time.

Also a massive thank you to Prof. Steven Piantadosi and Prof. Alan S. Kaufman for helping us understand this complicated topic. As well as to Jay Zagrosky from Boston University's Questrom School of Business for providing data from his study.

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References:
Kaufman, A. S. (2009). IQ testing 101. Springer Publishing Company.

Reynolds, C. R., & Livingston, R. A. (2021). Mastering modern psychological testing. Springer International Publishing.

Ritchie, S. (2015). Intelligence: All that matters. John Murray.

Spearman, C. (1961). " General Intelligence" Objectively Determined and Measured. - https://ve42.co/Spearman1904

Binet, A., & Simon, T. (1907). Le développement de l'intelligence chez les enfants. L'Année psychologique, 14(1), 1-94.. - https://ve42.co/Binet1907

Intelligence Quotient, Wikipedia - https://ve42.co/IQWiki

Radiolab Presents: G. - https://ve42.co/RadioLabG

McDaniel, M. A. (2005). Big-brained people are smarter: A meta-analysis of the relationship between in vivo brain volume and intelligence. Intelligence, 33(4), 337-346. - https://ve42.co/McDaniel2005

Deary, I. J., Strand, S., Smith, P., & Fernandes, C. (2007). Intelligence and educational achievement. Intelligence, 35(1), 13-21. - https://ve42.co/Deary2007

Lozano-Blasco, R., Quílez-Robres, A., Usán, P., Salavera, C., & Casanovas-López, R. (2022). Types of Intelligence and Academic Performance: A Systematic Review and Meta-Analysis. Journal of Intelligence, 10(4), 123. - https://ve42.co/Blasco2022

Kuncel, N. R., & Hezlett, S. A. (2010). Fact and fiction in cognitive ability testing for admissions and hiring decisions. Current Directions in Psychological Science, 19(6), 339-345. - https://ve42.co/Kuncel2010

Laurence, J. H., & Ramsberger, P. F. (1991). Low-aptitude men in the military: Who profits, who pays?. Praeger Publishers. - https://ve42.co/Laurence1991

Gregory, H. (2015). McNamara's Folly: The Use of Low-IQ Troops in the Vietnam War; Plus the Induction of Unfit Men, Criminals, and Misfits. Infinity Publishing.

Gottfredson, L. S., & Deary, I. J. (2004). Intelligence predicts health and longevity, but why?. Current Directions in Psychological Science, 13(1), 1-4. - https://ve42.co/Gottfredson2004

Sanchez-Izquierdo, M., Fernandez-Ballesteros, R., Valeriano-Lorenzo, E. L., & Botella, J. (2023). Intelligence and life expectancy in late adulthood: A meta-analysis. Intelligence, 98, 101738. - https://ve42.co/Izquierdo2023

Zagorsky, J. L. (2007). Do you have to be smart to be rich? The impact of IQ on wealth, income and financial distress. Intelligence, 35(5), 489-501. - https://ve42.co/Zagorsky2007

Strenze, T. (2007). Intelligence and socioeconomic success: A meta-analytic review of longitudinal research. Intelligence, 35(5), 401-426. - https://ve42.co/Strenze2007

Deary, I. J., Pattie, A., & Starr, J. M. (2013). The stability of intelligence from age 11 to age 90 years: the Lothian birth cohort of 1921. Psychological science, 24(12), 2361-2368. - https://ve42.co/Deary2013

Flynn, J. R. (1987). Massive IQ gains in 14 nations: What IQ tests really measure. Psychological bulletin, 101(2), 171. - https://ve42.co/Flynn1987

Why our IQ levels are higher than our grandparents' | James Flynn, TED via YouTube - https://www.youtube.com/watch?v=9vpqilhW9uI

Duckworth, A. L., Quinn, P. D., Lynam, D. R., Loeber, R., & Stouthamer-Loeber, M. (2011). Role of test motivation in intelligence testing. Proceedings of the National Academy of Sciences, 108(19), 7716-7720. - https://ve42.co/Duckworth2011

Kulik, J. A., Bangert-Drowns, R. L., & Kulik, C. L. C. (1984). Effectiveness of coaching for aptitude tests. Psychological Bulletin, 95(2), 179. - https://ve42.co/Kulik1984

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Special thanks to our Patreon supporters:
Adam Foreman, Amadeo Bee, Anton Ragin, Balkrishna Heroor, Benedikt Heinen, Bernard McGee, Bill Linder, Burt Humburg, Dave Kircher, Diffbot, Evgeny Skvortsov, Gnare, John H. Austin, Jr., john kiehl, Josh Hibschman, Juan Benet, KeyWestr, Lee Redden, Marinus Kuivenhoven, MaxPal, Meekay, meg noah, Michael Krugman, Orlando Bassotto, Paul Peijzel, Richard Sundvall, Sam Lutfi, Stephen Wilcox, Tj Steyn, TTST, Ubiquity Ventures

▀▀▀
Written by Derek Muller, Casper Mebius, & Petr Lebedev
Edited by Trenton Oliver
Filmed by Derek Muller, Han Evans, & Raquel Nuno
Animation by Fabio Albertelli & Ivy Tello
Additional video/photos supplied by Getty Images & Pond5
Music from Epidemic Sound
Produced by Derek Muller, Casper Mebius, & Han Evans

How the brain works, how we learn, and why we sometimes make stupid mistakes.
Submit ideas: http://ve42.co/GotIdeas
Apply to work with me: http://ve42.co/JoinUs

Thanks to Patreon supporters:
Nathan Hansen, Donal Botkin, Tony Fadell, Zach Mueller, Ron Neal

Support Veritasium on Patreon: http://bit.ly/VePatreon

This video was inspired by the book Thinking Fast and Slow by Daniel Kahneman

Harpist: Lara Somogyi http://ve42.co/Lara
Animator: Jesse Agar http://ve42.co/ThisPlace
Filmed by Raquel Nuno

Music by Kevin MacLeod, http://incompetech.com "Sneaky Adventure" "Harlequin"