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The Memory Palace of Andy Drucker

Scott Aaronson:

Shtetl-Optimized: [W]e in MIT’s complexity theory group are doing everything we can to respond to the most pressing global challenges.  And nothing illustrates that commitment better than a beautiful recent paper by my PhD student Andy Drucker…. Briefly, what Andy has done is to invent—and demonstrate—a breakthrough method by which anyone, including you, can easily learn to multiply ten-digit numbers in your head, using only a collection of stock photos from Flickr to jog your memory…. [Y]ou’re not allowed to modify or rearrange the photos, or otherwise use them to record any information about the computation while you’re performing it.  You can only use the photos as aids to your own memory.

By using his method, Andy—who has no special mental-math training or experience whatsoever—was able to calculate 9883603368 x 4288997768 = 42390752785149282624 in his head in a mere seven hours….

[T]his method provides probably the most convincing demonstration so far that the human brain, unaided by pencil and paper, can indeed solve arbitrary problems in the class P (albeit thousands of times more slowly than a pocket calculator)…