How an unlikely physics paradox controls these counterintuitive structures. Use code veritasium at https://incogni.com/veritasium to get an exclusive 60% off.

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

▀▀▀
A huge thank you to Paul Ducarme and Bas Overvelde at AMOLF for showing us around.
Check out their research on counter-snapping structures here - https://ve42.co/CounterSnapping

For more on Braess’s Paradox, check out these great videos by Up and Atom (https://youtu.be/cALezV_Fwi0) and Steve Mould (https://www.youtube.com/watch?v=Cg73j3QYRJc)

▀▀▀
0:00 What happens if you cut this rope?
1:41 The Spring Paradox
4:59 New York’s Perplexing Discovery
6:29 Road Networks and Traffic Flow
8:40 Braess’s Paradox
14:29 Snapping
17:16 This object shrinks when you stretch it

▀▀▀
References:

Ducarme, P., Weber, B., Hecke, M. van, & Johannes. (2025). Exotic mechanical properties enabled by countersnapping instabilities. Proceedings of the National Academy of Sciences - https://ve42.co/CounterSnapping
Braess's Paradox via Wikipedia - https://ve42.co/BraessWiki
Braess, D., Nagurney, A., & Wakolbinger, T. (2005). On a Paradox of Traffic Planning. Transportation Science - https://ve42.co/Braess2005
Schäfer, B., Pesch, T., Manik, D., Gollenstede, J., Lin, G., Beck, H.-P., … Timme, M. (2022). Understanding Braess’ Paradox in power grids. Nature Communications - https://ve42.co/Schafer2022
Kolata, G. (1990). What if They Closed 42d Street and Nobody Noticed? New York Times - https://ve42.co/Kolata1990
Youn, H., Gastner, M. T., & Jeong, H. (2008). Price of Anarchy in Transportation Networks: Efficiency and Optimality Control. Physical Review Letters - https://ve42.co/Youn2008
Nicolaou, Z. G., & Motter, A. E. (2012). Mechanical metamaterials with negative compressibility transitions. Nature Materials - https://ve42.co/Nicolaou2012
Counter-Snapping replication package - https://ve42.co/CSPackage

Images & Video:

Earth Day Festivities via VHS Music Rarities - https://www.youtube.com/watch?v=0awPgHjn2nY
Earth Day Speeches - https://www.youtube.com/watch?v=RMDI3kXpeQ8
1990s New York via NYC Nostalgia - https://www.youtube.com/watch?v=0YaFxTw0VqM
42nd Street Closure via Trainluvr - https://www.youtube.com/watch?v=gELde63Fzio
42nd Street Traffic Operator - https://ve42.co/NYCTraffic
Dietrich Braess via opc.mfo.de - https://ve42.co/BraessOPC
Dietrich Braess via Wikipedia - https://ve42.co/BraessWikiPic
Belt Buckle via Mingda Hardware - https://ve42.co/BeltBuckle

▀▀▀
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, 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, and wolfee

▀▀▀
Writers: Gregor Čavlović & Derek Muller
Producer & Director: Gregor Čavlović
Editors: James Stuart & Trenton Oliver
Camera Operators: Sander Mook, Dylan Meanwell, Fabio Albertelli, Casper Mebius & Gregor Čavlović
Animator: Fabio Albertelli
Illustrator: Jakub Misiek
Additional Editor: Peter Nelson & James Horsley
Researchers: Darius Garewal & Gabe Strong
Thumbnail Designers: Ren Hurley & Ben Powell
Production Team: Rob Beasley Spence, Tori Brittain & Matthew Cavanagh
Executive Producers: Derek Muller & Casper Mebius

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

Take your personal data back with Incogni! Use code SCIENCE at this
link and get 60% off an annual plan: https://incogni.com/science

This electrowetting device is called OpenDrop. You can use it to move water around for microfluidics applications. Or you can make games with it like Snake, Frogger, Crossy Road and packman.

Buy open drop here:
https://gaudishop.ch/index.php/product-category/opendrop/

Get the OpenDrop code here:
https://github.com/GaudiLabs/OpenDrop

My code for Snake and Frogger is here:
https://github.com/steventhebrave/opendrop-code

You can buy my books here:
https://stevemould.com/books

Twitter: http://twitter.com/moulds
Instagram: https://www.instagram.com/stevemouldscience/
Facebook: https://www.facebook.com/stevemouldscience/
TikTok: https://www.tiktok.com/stevemould
Buy nerdy maths things: http://mathsgear.co.uk