Sunday, January 21, 2023
– Live Presentation with Tom Rokicki–
Session at 12 Noon Atlanta time
(check your time here)
Please join us starting 10 minutes before this session using the following button.
For published CoM presentations please visit the G4G YouTube channel
After this virtual CoM presentation on Zoom, we will meet for an informal social session in a different Zoom space where we can all see each other (see the blue button below). That Zoom meeting will start around 1pm ET.
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Twenty Moves Suffice for Rubik’s Cube
Despite having 43,252,003,274,489,856,000 different positions, the Rubik’s cube can always be solved in 20 moves or less. This result, known as God’s number, was finally proved more than 30 years after the invention of the cube. We present some history of the mathematical and computational exploration of the cube, highlighting Kociemba’s amazing subgroup-based algorithm that calculates near-optimal solutions. We turn this algorithm inside-out, to solve an entire coset of positions at the same time, enabling resolution of the diameter of the cube group with a reasonable amount of computation. We give some details of the effort and finally close with some recent results and open questions.
492,116, and the topic of this talk, proved that every position of the Rubik’s cube can be solved in 20 moves or less. He shares his joy of programming through multiple open source projects and by helping with the International Collegiate Programming Competitions.