Persi Diaconis - Magician turned mathematician and super-star debunker, who got us closer to a new (more implementable) concept of randomness as it relates to complexity. He did this by demonstrating experimentally that a coin-toss (the sacred cow of all previous studies of randomness) was not inherently random. In fact, his repeatable experiments demonstrated that a coin toss is a completely causal process, in which known starting parameters end in predictable and repeatable terminal conditions.
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