What really happens when you ask for directions?
The math behind Google Maps. Sponsored by boot.dev - Click this link https://boot.dev/?promo=VERITASIUM and use our code VERITASIUM to get 25% off your first payment for boot.dev.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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For those curious about the path-count estimate: we estimated the non-backtracking paths NYC→SF, using a sparse spatial network model with mean degree ≈ 2.5 and characteristic length ≈ √N.
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0:00 What is a ‘shortest path algorithm’?
3:30 Dijkstra’s 20 Minute Algorithm
6:30 The First Route Planner
10:31 A* Search Algorithm
12:40 Shortest Doesn’t Mean Fastest
15:08 Road Network Hierarchy
18:29 Mapping North America - Nested Dissection
25:17 How do map apps work?
28:04 Simplicity is pre-requisite for reliability
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Check out @twoswap's channel for some fantastic videos!
A big thank you to Ben Strasser and Julian Dibbelt who were incredibly gracious with their time and feedback.
Thank you to all the experts we interviewed for this video: Aaron Bernstein, Tim Roughgarden, Tomas Rokicki, Jon Kleinberg, Virginia Vassilevska Williams, Peter Sanders, and the team behind the SSSP Barrier Paper: Xinkai Shu, Ran Duan, Xiao Mao, Longhui Yin, Jiayi Mao
For more information on how you choose A*'s heuristic, check out Polylog's video: https://youtu.be/A60q6dcoCjw?si=5LHOmZ8ZKvR_kLcx
If you'd like more information on Minecraft's A*, check out RedLogic's video: https://youtu.be/Zg0Cxn8AVZA?si=DyECX4wmeuSb4c1n
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References: https://ve42.co/DijkstraRefs
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Special thanks to our Patreon supporters:
Adam Foreman, Albert Wenger, Alex Porter, Alexander Tamas, André Powell, Anton Ragin, Balkrishna Heroor, Bertrand Serlet, Blake Byers, Bruce, Bryan Ackermann, Chris Brewer, Data Don, Dave Kircher, David Johnston, David Tseng, EJ Alexandra, Evgeny Skvortsov, Garrett Mueller, Gnare, gpoly, Hayden Christensen, Hong Thai Le, Ibby Hadeed, Jeromy Johnson, Jesse Brandsoy, Juan Benet, Kelcey Steele, KeyWestr, Kyi, Lee Redden, Marinus Kuivenhoven, Mark Heising, Martin Paull, Meekay, meg noah, Michael Krugman, Moebiusol - Cristian, Orlando Bassotto, Parsee Health, Paul Peijzel, Richard Sundvall, Robson, Sam Lutfi, Shalva Bukia, Sinan Taifour, Tj Steyn, Ubiquity Ventures, Vahe Andonians, wolfee
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Writers: Sulli Yost
Producer & Director: Sulli Yost
Presenter: Henry van Dyck & Derek Muller
Editor: Jonny Lennard and Trenton Oliver
Additional Editor: James Stuart
Camera Operators: Sulli Yost & Henry van Dyck
Illustrators: Jakub Misiek & Maria Gusakovich
Animators: @twoswap, Andrew Neet, Jonny Lennard, Alex Drakoulis & Fabio Albertelli
Researchers: Aakash Singh Bagga & Callum Cuttle
Thumbnail Designers: Abdallah Rabah, Ren Hurley, Ben Powell & Daniel Ellacott
Production Team: Jess Bishop-Laggett, Glen Griffiths, Matthew Cavanagh & Anna Milkovic
Executive Producers: Casper Mebius, Gregor Čavlović & Derek Muller
Map data © OpenStreetMap contributors, available under the Open Database License: https://www.openstreetmap.org/copyright
Additional video/photos supplied by Getty Images and Pond5
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