John Rainwater
The fictitious mathematician John Rainwater was created as a student prank but has become known as the author of important results in functional analysis. At the University of Washington in 1952, John Rainwater was invented and enrolled in a mathematics course by graduate students who were in possession of a duplicate student-registration form. Later, mathematicians published under the pseudonym of John Rainwater. Papers were published under the name Rainwater mainly in functional analysis, particularly in the geometric theory of Banach spaces and in convex functions. Rainwater's theorem is an important result in summability theory and functional analysis. The University of Washington's seminar in functional analysis is called the Rainwater seminar, and the associated Rainwater notes have influenced Banach-space theory and convex analysis. The concept of a fictional pseudonym used by multiple people creating valuable mathematics is not unique. Most notably, Nicolas Bourbaki has been the collective pseudonym for a number of leading mathematicians writing in French for many decades. (Wikipedia).
