Working It Out. Math solves a mystery about the opening of "A Hard Day's Night."

The music of most hit songs is pretty well known, but sometimes there are
mysteries. One question that remained unanswered for over forty years is: What
instrumentation and notes make up the opening chord of the Beatles. "A Hard
Day.s Night"? Mathematician Jason Brown - a big Beatles fan - recently solved the puzzle using his musical knowledge and discrete Fourier transforms, mathematical transformations that help decompose signals into their basic parts.
These transformations simplify applications ranging from signal processing to multiplying large numbers, so that a researcher doesn.t have to be "working like a dog" to get an answer.