This mechanism shrinks when pulled
How an unlikely physics paradox controls these counterintuitive structures. Sponsored by Incogni - 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 Sign up to the Veritasium newsletter for weekly science updates - https://ve42.co/Newsletter ▀▀▀ 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 compre