Accidental Algorithms

Taking a break from the regularly scheduled French visuals, we turn to Brian Hayes' article Accidental Algorithms at American Scientist:

"What prompts me to write on this theme is a new and wholly unexpected family of algorithms that provide efficient methods for several problems that previously had only brute-force solutions. The algorithms were invented by Leslie G. Valiant of Harvard University, with extensive further contributions by Jin-Yi Cai of the University of Wisconsin. Valiant named the methods 'holographic algorithms,' but he also refers to them as 'accidental algorithms,' emphasizing their capricious, rabbit-from-the-hat quality; they seem to pluck answers from a tangle of unlikely coincidences and cancellations. I am reminded of the famous Sidney Harris cartoon in which a long series of equations on a blackboard hinges on the notation 'Then a miracle occurs.'"

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