Euler’s Beautiful Equation on His 300th

Today is the 300th birthday of the great mathematician Leonhard Euler. Julie J. Rehmeyer discusses his beautiful equation in Science News:

“Gentlemen, that is surely true, it is absolutely paradoxical; we cannot understand it, and we don’t know what it means. But we have proved it, and therefore we know it must be the truth.” —Benjamin Pierce, a Harvard mathematician, after proving Euler’s equation, e^[i(pi)] = –1, in a 19th-century lecture.

Sunday, April 15, is the 300th birthday of Leonhard Euler (pronounced “oiler”), one of the most important mathematicians ever to have lived. His works help form the foundation of nearly all areas of mathematics, including calculus, number theory, geometry, and applied math.

One of the many discoveries for which he is famous is the equation eip = –1 . In a 1988 poll, readers of the journal Mathematical Intelligencer chose this equation as the single most beautiful equation in all of mathematics. The equation weaves together four seemingly unrelated mathematical numbers, e, p, i, and –1, in an astonishingly simple way.

But what does eip = –1 really mean?