Harry Pollard (mathematician)

Harry Pollard (28 February 1919 – November 20, 1985) was an American mathematician. He received his Ph.D from Harvard University in 1942 under the supervision of David Widder. He then taught at Cornell University, and was Professor of Mathematics at Purdue University from 1961 until his death in 1985. He is known for his work on celestial mechanics, orthogonal polynomials and the n-body problem as well as for the several textbooks he authored or co-authored. In the theory of Orthogonal polynomials, Pollard solved a conjecture of Antoni Zygmund, establishing mean convergence of the partial sums in ${\displaystyle L^{p}}$ norms for the Legendre polynomials and Jacobi polynomials in a series of three papers in the Transactions of the American Mathematical Society. The first of these papers deals with the fundamental case of Legendre polynomials. The end point cases in Pollard's theorem was established by Sagun Chanillo.