Spinning magnets near copper sheets create levitation!
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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/

Do odd perfect numbers exist? 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.

Special thanks to our Patreon supporters! Join this list to help us keep our videos free, forever:
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A massive thank you to Prof. Pace Nielsen for all his time and help with this video.

A big thank you to Dr. Asaf Karagila, Pascal Ochem, Prof. Tianxin Cai, and Prof. William Dunham for their expertise and help.

To try GIMPS out yourself: https://ve42.co/GIMPS

These sources were particularly helpful:
Perfect numbers via MacTutor - https://ve42.co/MTPerfect
Cai, T. (2022). Perfect numbers and fibonacci sequences. World Scientific. - https://ve42.co/Cai2022
Dunham, W. (2022). Euler: The master of us all (Vol. 22). American Mathematical Society. - https://ve42.co/Dunham2022

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References:
https://www.youtube.com/watch?v=T0xKHwQH-4I&pp=ygUPcGVyZmVjdCBudW1iZXJz
https://www.youtube.com/watch?v=q8n15q1v4Xo&pp=ygUPcGVyZmVjdCBudW1iZXJz
Dickson, L. E. (1919). History of the Theory of Numbers.. (Vol. 1). Carnegie Institution of Washington.
Knill, O. (2007). The oldest open problem in mathematics. NEU Math Circle, December2. - https://ve42.co/Knill2007
Perfect number via Wikipedia - https://ve42.co/WikiPerfect
Introduction to Arithmetic via HalthiTrust - https://ve42.co/IntroArithmetic
Nicomachus of Gerasa via MacTutor - https://ve42.co/MTNicomachus
Sonja, B. (1988). The First Perfect Numbers and Three Types of Amicable Numbers in a Manuscript on Elementary Number Theory by Ibn Fellûs. Erdem, c. IV, 11. - https://ve42.co/Sonja1988
Ibn Fallus via Wikipedia - https://ve42.co/WikiFallus
Mersenne prime via Wikipedia - https://ve42.co/WikiMP
List of Known Mersenne Prime Numbers - https://ve42.co/ListOfMP
Marin Mersenne via MacTutor - https://ve42.co/MTMersenne
Leonhard Euler via Wikipedia - https://ve42.co/WikiEuler
Frank Nelson Cole via Wikipedia - https://ve42.co/WikiFNCole
GIMPS History via Mersenne.org - https://ve42.co/GIMPSHistory
EFF Cooperative Computing Awards via EFF - https://ve42.co/EFFAwards
Jonathan Pace via Primewiki - https://ve42.co/PWikiPace
Book with just one number sells out in Japan via BastillePost - https://ve42.co/PrimeBook
Predicted distribution of Mersenne primes via John D. Cook - https://ve42.co/JDCookMP
Euler’s Odd Perfect Numbers Theorem via Cantor's Paradise - https://ve42.co/EulerOPN
A Perfect (Math) Mystery via Medium - https://ve42.co/Machado2024
Brent, R. P., Cohen, G. L., & te Riele, H. J. (1991). Improved techniques for lower bounds for odd perfect numbers. Mathematics of Computation, 57(196), 857-868. - https://ve42.co/Brent1991
Ochem, P., & Rao, M. (2012). Odd perfect numbers are greater than 10¹⁵⁰⁰. Mathematics of Computation, 81(279), 1869-1877. - https://ve42.co/Ochem2012
Mathematicians Open a New Front on an Ancient Number Problem via Quantamagazine - https://ve42.co/QuantaSpoofs
Descartes number via Wikipedia - https://ve42.co/WikiDescartesNumber
Andersen, N., Durham, S., Griffin, M. J., Hales, J., Jenkins, P., Keck, R., ... & Wu, D. (2022). Odd, spoof perfect factorizations. Journal of Number Theory, 234, 31-47. - https://ve42.co/Andersen2022
Pomerance’s Heuristic that Odd Perfect Numbers are Unlikely via OddPerfect.org - https://ve42.co/Heuristic

Images & Video:
Clip of Piergiorgio Odifreddi - https://www.youtube.com/watch?v=y0paHEA8-gA
Euclid’s Elements 1 via Claymath - https://ve42.co/CM1
Euclid’s Elements 2 via Claymath - https://ve42.co/CM2
Euclid’s Elements 3 via Claymath - https://ve42.co/CM3
Diophanti - https://ve42.co/Diophanti
Gauss book - https://ve42.co/GaussDis
Euler’s Archive 1 - https://ve42.co/Euler1
Euler’s Archive 2 - https://ve42.co/Euler2

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Special thanks to our Patreon supporters:
Anton Ragin, Balkrishna Heroor, Bertrand Serlet, Bill Linder, Blake Byers, Burt Humburg, Chris Harper, Dave Kircher, David Johnston, Diffbot, Evgeny Skvortsov, Garrett Mueller, Gnare, I.H., John H. Austin, Jr., john kiehl, Josh Hibschman, Juan Benet, KeyWestr, Lee Redden, Marinus Kuivenhoven, Matthias Wrobel, Max Paladino, Meekay, meg noah, Michael Krugman, Orlando Bassotto, Paul Peijzel, Richard Sundvall, Sam Lutfi, Stephen Wilcox, Tj Steyn, TTST, Ubiquity Ventures, wolfee

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Directed by Casper Mebius
Written by Casper Mebius and Derek Muller
Edited by Peter Nelson
Illustrated by Jakub Misiek
Animated by Fabio Albertelli, Ivy Tello, David Szakaly, Alondra Vitae, Alex Drakoulis, and Leigh Williamson
Filmed by Derek Muller, Raquel Nuno, and Peter Nelson
Additional research by Aaron Santos, Camilla Machado, and Gregor Čavlović
Produced by Casper Mebius, Gregor Čavlović, Han Evans, and Derek Muller

Thumbnail by Ren Hurley
Additional video/photos supplied by Getty Images and Pond5
Music from Epidemic Sound

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

This video is sponsored by Brilliant. The first 200 people to sign up via https://brilliant.org/veritasium get 20% off a yearly subscription. To make antivenom, you first need to collect venom from the world’s most deadly snakes.

Huge thanks to the Australian Reptile Park for having us over to film – special thanks to Zac Bower for milking all of these snakes for us and Caitlin Vine for organizing the shoot. Absolute legends. https://www.reptilepark.com.au

Huge thanks to Dr Timothy Jackson from the Australian Venom Research Unit for answering our questions, and fact checking the script. This video would not have been the same without you.

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

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References:
Calmette, A. (1896). Le venin des serpents: Physiologie de l'envenimation, traitement des morsures venimeuses par le sérum des animaux vaccinés. Paris: Société d'éditions scientifiques.

Broad, A. J., Sutherland, S. K., & Coulter, A. R. (1979). The lethality in mice of dangerous Australian and other snake venom. Toxicon, 17(6), 661-664. – https://ve42.co/Broad79

WHO Expert Committee on Biological Standardization. (2016). WHO guidelines for the production, control and regulation of snake antivenom immunoglobulins. Geneve, Switzerland. – https://ve42.co/WHO2016

Calmette, A. (1896). The treatment of animals poisoned with snake venom by the injection of antivenomous serum. British medical journal, 2(1859), 399. – https://ve42.co/Calmette1896

Hawgood, B. J. (1999). Doctor Albert Calmette 1863–1933: founder of antivenomous serotherapy and of antituberculous BCG vaccination. Toxicon, 37(9), 1241-1258. – https://ve42.co/Hawgood99

Pucca, M. B., Cerni, F. A., Janke, R., Bermúdez-Méndez, E., Ledsgaard, L., Barbosa, J. E., & Laustsen, A. H. (2019). History of envenoming therapy and current perspectives. Frontiers in immunology, 1598. – https://ve42.co/Pucca19

Kang, T. S., Georgieva, D., Genov, N., Murakami, M. T., Sinha, M., Kumar, R. P., ... & Kini, R. M. (2011). Enzymatic toxins from snake venom: structural characterization and mechanism of catalysis. The FEBS journal, 278(23), 4544-4576. – https://ve42.co/Kang2011

Hawgood, B. J. (2007). Albert Calmette (1863–1933) and Camille Guerin (1872–1961): the C and G of BCG vaccine. Journal of medical biography, 15(3), 139-146. – https://ve42.co/Hawgood2007

Vonk, F. J., Admiraal, J. F., Jackson, K., Reshef, R., de Bakker, M. A., Vanderschoot, K., ... & Richardson, M. K. (2008). Evolutionary origin and development of snake fangs. Nature, 454(7204), 630-633. – https://ve42.co/vonk2008

Bochner, R. (2016). Paths to the discovery of antivenom serotherapy in France. Journal of Venomous Animals and Toxins including Tropical Diseases, 22. – https://ve42.co/Bochner2016

Young, B. A., Herzog, F., Friedel, P., Rammensee, S., Bausch, A., & van Hemmen, J. L. (2011). Tears of venom: hydrodynamics of reptilian envenomation. Physical review letters, 106(19), 198103. – https://ve42.co/Young2011

Madras Medical Journal, Volume Second, July-December 1870. Page 355

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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, Benedikt Heinen, 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 Petr Lebedev and Derek Muller
Edited by Trenton Oliver
Filmed by Jason Tran and Petr Lebedev
Animation by Fabio Albertelli, Jakub Misiek, Ivy Tello and Mike Radjabov.
Molecule animation by Reciprocal Space – https://www.reciprocal.space
Additional video/photos supplied by Getty Image
B-roll supplied by Seqirus Australia
Music from Epidemic Sound and Jonny Hyman
Thumbnail by Ignat Berbeci
Produced by Derek Muller, Petr Lebedev, and Emily Zhang

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 an SAT question became a mathematical paradox.

How can you Yo-Yo without the string attached?
Check out Audible: http://bit.ly/AudibleVe
For more Ben Conde: http://bit.ly/VeBenConde
For Beyond Slow Motion: http://bit.ly/VeBeyondSlowMo

For more on yo-yos check out: http://bit.ly/290wR3a

How to yo-yo without a string attached... So many crazy tricks and the science that makes it possible.

Edited and animated by Daniel Joseph Files

If you've seen footage from the International Space Station or any of the space shuttle missions, you know that astronauts float around as they orbit the Earth. Why is that? Is it because the gravitational force on them is zero in space? (Or nearly zero?) The truth is that the strength of the gravitational attraction is only slightly less than it is on Earth's surface. So how are they able to float? Well, they aren't floating - they're falling, along with the space station. They don't crash into the Earth because they have a huge orbital velocity. So as they accelerate towards the Earth, the Earth curves away beneath them and they never get any closer. Since the astronauts have the same acceleration as the space station, they feel weightless. It's like being in a free-falling elevator (without the disastrous landing).

Director of Photography: Stefan Smith
Camera Assistant: Raa Perajeev
Boom Operator: Maha Sivalingam

Production Coordinator: Adrian Tan
Production Assistants: James Peniata, Pratheep Ramachandran

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

How an unlikely physics paradox controls these counterintuitive structures.

The number 37 is on your mind more than you think. Head to https://brilliant.org/veritasium to start your free 30-day trial and get 20% off an annual premium subscription.

Huge thanks to Tom Magliery for sharing his 37 collection with us. Support http://thirty-seven.org by sharing your own 37 sightings to tom@thirty-seven.org!
Thanks to Dr. Todd Landman, the Academic Magician, for sharing his footage of the 37 Force. - https://www.todd-landman.com/

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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

Sam Lutfi, Lee Redden, Juan Benet, Richard Sundvall, Paul Peijzel, Gnare, Michael Krugman, Meekay, Ubiquity Ventures, Marinus Kuivenhoven, Bill Linder, Evgeny Skvortsov, Burt Humburg, Dave Kircher, Diffbot, john kiehl, Blake Byers, Stephen Wilcox, John H. Austin, Jr., Josh Hibschman, TTST, Orlando Bassotto, Anton Ragin, David Johnston, KeyWestr, Tj Steyn, meg noah, Chris Harper, Adam Foreman, Max Paladino, Balkrishna Heroor, I. H., Garrett Mueller, Bertrand Serlet, Kyi, wolfee, Matthias Wrobel

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:
Simon, W. E. (1972). “Blue Seven Phenomenon” in Elementary and Jr. High Children. Psychological Reports - https://ve42.co/Simon1972
Trueman, J. (1979). Existence & Robustness of Blue Seven Phenomena. The Journal of General Psychology - https://ve42.co/Trueman1979
Saito, M. (1999). “Blue and Seven Phenomena” in Japanese Students. Perceptual & Motor Skills - https://ve42.co/Saito1999
Philbrick, J. L. (1976). Blue seven in East Africa: Preliminary report. Perceptual & Motor Skills - https://ve42.co/Philbrick1976
Hargreaves, S. (2009). The psychology of randomness. - https://ve42.co/Hargreaves2009
The 37 Force via The Magician’s Forum - https://ve42.co/37Force1
Fulves, K. (1979) Self-Working Mental Magic. Dover Publications, Inc. - https://ve42.co/Fulves1979
Random numbers via The Jargon File at catb.org - https://ve42.co/Jargon
Random Number Survey by MahoganyForest via Reddit - https://ve42.co/RedditRndm
Prime number theorem via Wikipedia - https://ve42.co/WikiPNT
Grossack, C. (2023). A truly incredible fact about the number 37. Grossack.site - https://ve42.co/Grossack2023
Least prime factor of n via oeis.org - https://ve42.co/LeastPrime
Fry, H. (2017). When should you settle down? ideas.ted.com - https://ve42.co/Fry2017
Choosing Toilets by Numberphile - https://www.youtube.com/watch?v=XIOoCKO-ybQ
Seaton, R. (2014). The Secretary Problem Explained: Dating Mathematically. rs.io - https://ve42.co/Seaton2014

Images & Video:
Just 37 by Tom Magliery - https://ve42.co/Just37
R4000 Processor via Molecular Expressions - https://ve42.co/micro37
The “37” Cluster by Noel Carboni - https://ve42.co/NGC2169
Charles Fleischer via Wikimedia - https://ve42.co/Fleischer

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Directed by Emily Zhang
Written by Emily Zhang and Derek Muller
Edited by Peter Nelson
Asst edited by Luke Molloy
Animated by Fabio Albertelli, Ivy Tello, and Leigh Williamson
Illustrated by Jakub Misiek
Filmed by Emily Zhang, Casper Mebius, Derek Muller, Michael Cimpher, and David Szasz
Additional research by Gregor Čavlović
Produced by Emily Zhang, Giovanna Utichi, Han Evans, and Emily Taylor

Thumbnail contributions by Ignat Berbeci, Ren Hurley, and Peter Sheppard
Additional video/photos supplied by Getty Images and Storyblocks
Music from Epidemic Sound

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

I saw my first wild koalas while driving on the great ocean road. Generally their days are not very exciting. They spend most of their time sleeping and the rest of the time eating eucalyptus leaves. The eucalyptus leaves are tough to digest which explains their consumate napping. Plus they require bacteria in their gut to help them break down their food. This bacteria must be passed down from mother to child through the mother's poo. It's a tough start to life for koalas!

I used a nitrogen membrane and Stirling cryocooler to liquefy nitrogen out of the air. For this video I partnered with Starbucks to celebrate their Nitro Cold Brew. Order one here: https://starbucks.app.link/derekmuller

Making liquid nitrogen is hard - in fact up until 150 years ago scientists doubted whether it was even possible to liquefy nitrogen. In 1823, At the royal institution in London, Michael Faraday first produced liquid chlorine, kind of accidentally by putting it under high pressure. He similarly liquefied ammonia.

Borrowing a mixture from Thilorier in France, a combination of dry ice, snow and ether, he reached a temperature of -110C. By 1845 he used this mixture plus a hand pump to pressurize gases to liquefy all the known gases except six, which included oxygen and nitrogen. These became known as the “permanent” gases.

A French Physicist Aimé compressed oxygen and nitrogen in tanks and then lowered them into the ocean over 1.6km deep, where the pressure got up to 200 atmospheres. Still the gases didn’t liquefy.

Only at the end of 1877 were the first droplets of liquid oxygen and liquid nitrogen produced, by Cailletet in France. He first tried oxygen by compressing it up to 300 atmospheres, cooled to -30C, but that wasn't even enough to liquefy oxygen. But when he suddenly released the pressure, the expanding gas cooled, he estimated to -200C and he saw a mist and then droplets slide down the walls of his vessel.

It's amazing how far we've come in that now I can purchase a helium-based cryocooler. It compresses and expands the gas to absorb heat from the tip of the cold finger and eject it into the surroundings at ambient temperature.

LSD-fiend, surfer, maverick — Kary Mullis might be the weirdest person ever to win the Nobel Prize. Get a little smarter every day with Brilliant. Visit https://brilliant.org/veritasium to get 20% off your annual premium subscription.

A massive thank you to Tom White, Hudson Freeze, and Henry Erlich for their time and expertise on the subject.

A huge thank you to Eleni Kleanthous, Jan Novoselec, Kieran Sparkes, Andrew Garcia, and UCSD’s Pride Lab for reviewing the science.

For great coverage of the PCR story, check out ‘Making PCR’ by Paul Rabinow - https://ve42.co/Rabinow1996

For exclusive behind-the-scenes content on the making of this video, join us on Patreon: https://www.patreon.com/posts/119438561

00:00 DNA under a microscope
01:17 Kary Mullis at Berkeley
02:50 Cetus and early biotech
04:16 How to detect sickle cell anemia
09:12 Kary Mullis at Cetus
10:39 Infinite DNA glitch explained
15:29 Kary Mullis struggles
18:10 Thermus Aquaticus to the rescue
23:53 Going public
26:59 The quirky genius, Kary Mullis

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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, 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, Tj Steyn, TTST, Ubiquity Ventures, and 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:
Mullis, K. (1968). Cosmological Significance of Time Reversal. Nature - https://ve42.co/Mullis1968
Mullis, K. (1997). Dancing Naked in the Mind Field. Vintage - https://ve42.co/Mullis1997
McDonald, C. (2019). Intolerable Genius. Cal Alumni Association - https://ve42.co/McDonald2019
Conner, B. J. et al. (1983). Detection of sickle cell beta S-globin allele by hybridization with synthetic oligonucleotides. Proceedings of the National Academy of Sciences - https://ve42.co/Conner1983
Human Beta-globin gene via UniProt - https://ve42.co/BetaGlobin
Saiki, R. K. et al. (1985). Enzymatic Amplification of β-Globin Genomic Sequences and Restriction Site Analysis for Diagnosis of Sickle Cell Anemia. Science - https://ve42.co/Saiki1985
Mullis, K. B. (1990). The Unusual Origin of the Polymerase Chain Reaction. Scientific American - https://ve42.co/Mullis1990
Kary B. Mullis via The Nobel Prize - https://ve42.co/Nobel1993
Restriction Enzymes via The Nobel Prize - https://ve42.co/Nobel1978
Saiki, R. K. et al. (1988). Primer-Directed Enzymatic Amplification of DNA with a Thermostable DNA Polymerase. Science - https://ve42.co/Saiki1988
Smith, T. C. (2024). HIV Denial in the COVID Era. AIDS and Behavior. - https://ve42.co/Smith2024
Mullis, K. B., Faloona, F. A. (1987). Specific synthesis of DNA in vitro via a polymerase-catalyzed chain reaction. Methods in Enzymology - https://ve42.co/Mullis1987
Dr. Kary Mullis about LSD via RadioIciMaintenant Rim - https://ve42.co/MullisLSD
Brock, T. D., & Freeze, H. (1969). Thermus aquaticus gen. n. and sp. n., a Nonsporulating Extreme Thermophile. Journal of Bacteriology - https://ve42.co/Brock1969
Rediscovering Yellowstone via UW-Madison - https://ve42.co/Madison2017
Presidential Aids Advisory Panel Report via gov.za - https://ve42.co/Mbeki2001
Nattrass, N. (2008). AIDS and the Scientific Governance of Medicine in Post-Apartheid South Africa. African Affairs - https://ve42.co/Nattrass2008
Chigwedere, P. et al. (2008). Estimating the Lost Benefits of Antiretroviral Drug Use in South Africa. JAIDS Journal of Acquired Immune Deficiency Syndromes - https://ve42.co/Chigwedere2008

Images & Video:
Available here - https://ve42.co/PCRVisuals

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Directed by Gregor Čavlović and Latif Nasser
Written by Gregor Čavlović, Latif Nasser, and Derek Muller
Edited by Peter Nelson
Animated by Ivy Tello, Emma Wright, Fabio Albertelli, Andrew Neet, and Alex Drakoulis
Illustrated by Emma Wright, Maria Gusakovich, and Jakub Misiek,
Filmed by Derek Muller, Alex Gorosh, and Gregor Čavlović
Additional research by Geeta Thakur and Gabriel Strong
Produced by Derek Muller, Latif Nasser, Gregor Čavlović, Rob Beasley Spence, Emily Lazard, Tori Brittain, James Horsley, Luke Lewis, Matthew Cavanagh, Barbara Abraul, Henry Van Dyck, Petr Lebedev, and Casper Mebius

Thumbnail contributions by Ben Powell, Ren Hurley, Peter Sheppard, Maria Gusakovich, Emma Wright, Jakub Misiek, and Tommy Steven

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

In 2018 the kg will be defined by Planck's constant, not a hunk of metal.
Try a free book from Audible for 30 days http://ve42.co/audible
Special thanks to the staff at NIST who made this possible: Darine Haddad, Jon Pratt, Stephan Schlamminger, and Ben Stein.

Additional footage and animations by Sean Kelley, Jennifer Lauren Lee, and Frank Seifert.

I have been obsessed with measurement for a long time and I'm not sure quite how it happened. The world's roundest object played a role in this. I guess I'm just fascinated by how difficult it is to pin down a quantity like a kilogram. A physical object seemed like a good idea until the mass of the international prototype kilogram wasn't as constant as expected. These methods of the Kibble balance and silicon sphere have shown better precision than 20 parts per billion, making them superior to the old method. The agreement between Avogadro approaches

Special thanks to Patreon Supporters:
Tony Fadell, Donal Botkin, Jeff Straathof, Zach Mueller, Ron Neal, Nathan Hansen

Support Veritasium on Patreon: http://ve42.co/patreon

Interferometer video by TSG Physics: https://www.youtube.com/watch?v=j-u3IEgcTiQ

Music from http://epidemicsound.com "ExperiMental1" by Gunnar Johnsén

Studio filming by Raquel Nuno

When we touch something that is hot or cold, what are we actually sensing? Is it the temperature of the object, or the rate at which heat flows between the object and our hand?

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:
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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

Discover the explosive story of Alfred Nobel. Sponsored by Opera - Upgrade your browsing experience with Opera today. Download it right here: https://opr.as/Opera-browser-veritasium

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

CORRECTIONS:
30:36 The molecular chain we showed here when talking about cellulose was actually starch, the glycosidic bonds should be bent (beta) not straight (alpha) bonds - Thank you to someriversong1793 for spotting this
37:38 The animation shows the casing flying away with the bullet, this is incorrect, only the bullet accelerates down the barrel like that - Thank you to kettusnuhveli for pointing this out

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A huge thank you to Jesse Taylor for making the demonstrations possible and sharing his experience with us!

And a big thanks to Dr. Katharine Tibbets, Dr. Julien Glorian & Sabrina DePiero for their expertise and participation in this video.

Also thanks to Steven Johnson, author of The Infernal Machine (as featured on 99% Invisible) and to Jonah Sachs and professor Terry Reynolds for their help on the project

▀▀▀
0:00 The Nobel Armament Factory
4:18 Gunpowder vs Nitroglycerine
10:58 How safe is nitroglycerin?
14:50 Blast Caps
19:09 Why does nitroglycerin explode on impact?
22:19 The invention of dynamite
26:56 Dynamite vs TNT
27:53 Explosive Cotton - Gelignite
32:43 The Merchant of Death
35:42 Smokeless Guns
38:04 The Birth of Terror
42:08 Why did Nobel start the prize?
43:11 What happened to Nobel?

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References: https://ve42.co/NobelRefs

Images & Video: https://ve42.co/NobelImRefs

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Special thanks to our Patreon supporters:


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

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Writer, Director & Producer: Henry van Dyck
Presenters: Derek Muller & Henry van Dyck
Editor: Trenton Oliver
Camera Operators: Wesley Wright, Prescott McCarthy, Joel Schöppe & Henry van Dyck
Animators: Andrew Neet, Fabio Albertelli, Emma Wright, Rokas Viksraitis, Saif Javed & Ivy Tello
Illustrators: Jakub Misiek, Maria Gusakovich, Nataly Zhuk, Isaac McRee, Grace Nemanic, Sofia Constantini & Veronika Pasynkova
Additional Editors: James Stuart, Peter Nelson & Spencer Wright
Researchers: Aakash Singh Bagga & Gabe Strong
Thumbnail Designers: Abdallah Rabah, Ren Hurley, Ben Powell & Henry van Dyck
Production Team: Josh Pitt, Nicola Griffiths, Rob Beasley Spence, Matthew Cavanagh, Anna Milkovic & Zoe Heron
Executive Producers: Casper Mebius & Derek Muller

Additional video/photos supplied by Getty Images, The David Rumsey Historical Map Collection, Pond5 & StoryBlocks
Music from Epidemic Sound

The beautiful math behind six degrees of separation. Sponsored by Incogni - use code veritasium at https://incogni.com/veritasium to get an exclusive 60% off.

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

To play around with the simulations in the video, you can follow these links:
Disease spreading - https://www.veritasium.com/simulation2
Preferential attachment - https://ve42.co/barabasiAlbertSim


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A huge thank you to:
Duncan Watts, for creating the small-world model that inspired this video and expanding on his further work; Steve Strogatz, for telling the story with such clarity & humour; Albert-László Barabási, for revealing the the inevitability and impact of hubs; Mark Buchanan, for his insightful takeaways that pulled it all together.

Check out Duncan Watts’ books here - https://www.amazon.com/Six-Deg....rees-Science-Connect
Check out Mark Buchanan’s book here - https://ve42.co/bookNexusWorlds

▀▀▀
Chapters:
0:00 What is six degrees of separation?
4:23 Network Shortcuts
7:11 The Strength of Weak Ties
8:20 Proving it’s a small world
10:39 How quickly can disease spread?
12:36 Strogatz goes viral
16:59 What is a network hub?
18:23 Preferential Attachment
23:38 The Prisoner’s Dilemma
28:22 Your behavior can change the world’s


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

Image and video references can be found here - https://ve42.co/networksVisuals

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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, KeyWestr, Kyi, Marinus Kuivenhoven, Matthias Wrobel, meg noah, Michael Bush, Michael Krugman, Robert Oliveira, Tj Steyn & wolfee

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Writers: James Moore, Casper Mebius & Derek Muller
Producer & Director: James Moore
Editors: Peter Nelson & Jack Saxon
Camera Operators: Derek Muller & Casper Mebius
Animators: Andrew Neet, Emma Wright, Fabio Albertelli & Ivy Tello
Illustrators: Jakub Misiek
Assistant Editor: James Stuart
Researchers: Callum Cuttle, Aakash Singh Bagga & Gabe Strong
Simulations: Callum Cuttle, Gabe Strong & Ivy Tello
Sound Designers: Pavle Peric & James Stuart
Thumbnail Designers: Abdallah Rabah, Ren Hurley & Ben Powell
Production Team: Josh Pitt, Nicola Griffiths & Rob Beasley Spence
Executive Producers: Derek Muller & Casper Mebius
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Music from Epidemic Sound

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

▀▀▀
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

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

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

▀▀▀
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

▀▀▀
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

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

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’

Most people recognize that atoms are the fundamental building blocks of all matter around us. An atom itself is composed of protons, neutrons and electrons. The simplest atom is the hydrogen atom because it consists of only one proton and one electron. If a neutron is added to the nucleus, the atom is still hydrogen, just a more massive version. Atoms of the same element (i.e. those with the same number of protons) but different numbers of neutrons are called isotopes.

Dr Ken Libbrecht is the world expert on snowflakes, designer of custom snowflakes, snowflake consultant for the movie Frozen - his photos appear on postage stamps all over the world. This video is sponsored by Brilliant. The first 200 people to sign up via https://brilliant.org/veritasium get 20% off a yearly subscription.

Thanks to Dr Ken Libbrecht for showing us how to grow designer snowflakes. Obviously, this video would not have been possible without his help and his expertise. His website is full of information about snowflakes http://snowcrystals.com. His new book is also available to purchase from here -- https://ve42.co/SnowCrystalsBook

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References:
Libbrecht, K. G. (2019). A Quantitative Physical Model of the Snow Crystal Morphology Diagram. arXiv preprint arXiv:1910.09067. -- https://ve42.co/Libbrecht2019

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Written by Derek Muller
Filmed by Derek Muller, Raquel Nuno, Trenton Oliver and Emily Zhang
Edited by Trenton Oliver
Animations by Ivy Tello and Trenton Oliver
Additional video supplied by Getty Images
Music from Epidemic Sound
Produced by Derek Muller, Petr Lebedev and Emily Zhang