Andrew Stothers, a Mathematics PhD graduate from the University of Edinburgh, is being praised for finding a fundamental breakthrough in matrix multiplication.
The number of steps needed to multiply two n x n matrices is about n3 for the naive computer programmer, but can it be improved by some clever thinking? The previous best answer to this was in 1987, where an algorithm was found which did the multiplication in n2.376 steps. This remained the best possible until 2010, when Andrew Stothers managed to get the exponent down to 2.374.
Read more about the story in this New Scientist article, which also describes how another mathematician - Virginia Vassilevska-Williams - has now got the exponent down to 2.373, building on Andrew's work.