Topic #8 ----------- OP-SF NET 16.6 ---------- November 15, 2009
From: Tom Koornwinder
Subject: Passings of Gel'fand and Gohberg

I.M. Gel'fand (1913-2009) and I. Gohberg (1928-2009), two giants of 20th century mathematics, died during October. Gelfand contributed to
many subjects including special functions. MathSciNet gives 42 hits for papers by him with "hypergeometric" in the title. His paper
"General theory of hypergeometric functions" (Russian), Dokl. Akad. Nauk SSSR 288 (1986), no. 1, 14-18, laid the foundation for what are
Now called Gelfand hypergeometric functions or A-hypergeometric functions. For further information on Gel'fand, see News Archive 2009 at 

Gohberg was a very broad and productive analyst, in particular in operator theory. But his work touches on orthogonal polynomials. As a
student of Krein, some of his work dealt with Krein's matrix-valued orthogonal polynomials. Gohberg concentrated on the case of the unit
circle and with indefinite inner product. See some of the chapters in I. Gohberg, P. Lancaster and L. Rodman, "Indefinite linear algebra and
applications", Birkh�user, 2005. For more information on Gohberg, see