Richard Steven Varga (October 9, 1928 - February 25, 2022) was an American mathematician who specialized in

numerical analysis Numerical analysis is the study of algorithms that use numerical approximation (as opposed to symbolic computation, symbolic manipulations) for the problems of mathematical analysis (as distinguished from discrete mathematics). It is the study of ...

and

linear algebra Linear algebra is the branch of mathematics concerning linear equations such as :a_1x_1+\cdots +a_nx_n=b, linear maps such as :(x_1, \ldots, x_n) \mapsto a_1x_1+\cdots +a_nx_n, and their representations in vector spaces and through matrix (mathemat ...

. He was an Emeritus University Professor of Mathematical Sciences at

Kent State University Kent State University (KSU) is a Public university, public research university in Kent, Ohio, United States. The university includes seven regional campuses in Northeast Ohio located in Kent State University at Ashtabula, Ashtabula, Kent State ...

and an adjunct Professor at

Case Western Reserve University Case Western Reserve University (CWRU) is a Private university, private research university in Cleveland, Ohio, United States. It was established in 1967 by a merger between Western Reserve University and the Case Institute of Technology. Case ...

. Varga was known for his contributions to many areas of mathematics, including

matrix analysis In mathematics, particularly in linear algebra and applications, matrix analysis is the study of matrices and their algebraic properties. Some particular topics out of many include; operations defined on matrices (such as matrix addition, matrix mu ...

complex analysis Complex analysis, traditionally known as the theory of functions of a complex variable, is the branch of mathematical analysis that investigates functions of complex numbers. It is helpful in many branches of mathematics, including algebraic ...

approximation theory In mathematics, approximation theory is concerned with how function (mathematics), functions can best be approximation, approximated with simpler functions, and with quantitative property, quantitatively characterization (mathematics), characteri ...

, and

scientific computation Computational science, also known as scientific computing, technical computing or scientific computation (SC), is a division of science, and more specifically the Computer Sciences, which uses advanced computing capabilities to understand and so ...

. He was the author of the classic textbook ''Matrix Iterative Analysis''. Varga served as the Editor-in-Chief of the journal ''

Electronic Transactions on Numerical Analysis ''Electronic Transactions on Numerical Analysis'' is a peer-reviewed scientific open access journal publishing original research in applied mathematics with the focus on numerical analysis and scientific computing. It is published by the Ken ...

'' (ETNA).

Birth and education

Richard Varga was born in

Cleveland Cleveland is a city in the U.S. state of Ohio and the county seat of Cuyahoga County. Located along the southern shore of Lake Erie, it is situated across the Canada–U.S. maritime border and approximately west of the Ohio-Pennsylvania st ...

Ohio Ohio ( ) is a U.S. state, state in the Midwestern United States, Midwestern region of the United States. It borders Lake Erie to the north, Pennsylvania to the east, West Virginia to the southeast, Kentucky to the southwest, Indiana to the ...

of Hungarian-born parents in 1928. He obtained a bachelor's degree in mathematics from Case Institute of Technology (present

) in 1950. Varga was a member of the

collegiate wrestling Collegiate wrestling, commonly referred to as folkstyle wrestling, is the form of wrestling practiced at the post-secondary level in the United States. This style of wrestling is also practiced at the high school, middle school, and elementary ...

team of Case. Following the advice of Professor Max Morris at Case, Varga joined

Harvard University Harvard University is a Private university, private Ivy League research university in Cambridge, Massachusetts, United States. Founded in 1636 and named for its first benefactor, the History of the Puritans in North America, Puritan clergyma ...

for the master's degree and obtained an A.M. in mathematics. Continuing his doctoral work at Harvard under the supervision of

Joseph L. Walsh __NOTOC__ Joseph Leonard Walsh (September 21, 1895 – December 6, 1973) was an American mathematician who worked mainly in the field of analysis. The Walsh function and the Walsh–Hadamard code are named after him. The Grace–Walsh–Szeg� ...

, Varga worked on the theory of rational approximation of

complex Complex commonly refers to: * Complexity, the behaviour of a system whose components interact in multiple ways so possible interactions are difficult to describe ** Complex system, a system composed of many components which may interact with each ...

analytic function In mathematics, an analytic function is a function that is locally given by a convergent power series. There exist both real analytic functions and complex analytic functions. Functions of each type are infinitely differentiable, but complex ...

s. Varga received his

Ph.D. A Doctor of Philosophy (PhD, DPhil; or ) is a terminal degree that usually denotes the highest level of academic achievement in a given discipline and is awarded following a course of graduate study and original research. The name of the deg ...

degree in 1954 with a dissertation ''Properties of a Special Set of

Entire Functions In complex analysis, an entire function, also called an integral function, is a complex-valued function that is holomorphic on the whole complex plane. Typical examples of entire functions are polynomials and the exponential function, and any fini ...

and their Respective

Partial Sums In mathematics, a series is, roughly speaking, an addition of infinitely many terms, one after the other. The study of series is a major part of calculus and its generalization, mathematical analysis. Series are used in most areas of mathematics ...

''. While at Harvard, Varga also studied with

Garrett Birkhoff Garrett Birkhoff (January 19, 1911 – November 22, 1996) was an American mathematician. He is best known for his work in lattice theory. The mathematician George Birkhoff (1884–1944) was his father. Life The son of the mathematician Ge ...

, who later came to collaborate with Varga in research both on

iterative method In computational mathematics, an iterative method is a Algorithm, mathematical procedure that uses an initial value to generate a sequence of improving approximate solutions for a class of problems, in which the ''i''-th approximation (called an " ...

s for differential equations and on positive matrices (and

positive operator In mathematics (specifically linear algebra, operator theory, and functional analysis) as well as physics, a linear operator A acting on an inner product space is called positive-semidefinite (or ''non-negative'') if, for every x \in \operatorname( ...

s on partially ordered vector spaces).

Career

From 1954 until 1960, Varga worked for

Bettis Atomic Power Laboratory Bettis Atomic Power Laboratory is a U.S. Government-owned research and development facility in the Pittsburgh suburb of West Mifflin, Pennsylvania, that works exclusively on the design and development of nuclear power for the U.S. Navy. It was one ...

in Pittsburgh. In 1960 he returned to

Case Institute of Technology Case Western Reserve University (CWRU) is a Private university, private research university in Cleveland, Ohio, United States. It was established in 1967 by a merger between Western Reserve University and the Case Institute of Technology. Case ...

as a professor of mathematics and remained there for the next nine years. He then moved to Kent State University as University Professor of mathematics. At Kent Varga has held numerous academic positions, including director (1980–1988) and research director (1988–2006) of the Institute for Computational Mathematics. His work includes numerical analysis—particularly iterative methods in

numerical linear algebra Numerical linear algebra, sometimes called applied linear algebra, is the study of how matrix operations can be used to create computer algorithms which efficiently and accurately provide approximate answers to questions in continuous mathemati ...

, matrix theory, and differential equations—complex approximation theory, particularly Padé approximation (often with Edward B. Saff, Jr.)—and analytic number theory, including high-precision calculations related to the

Riemann hypothesis In mathematics, the Riemann hypothesis is the conjecture that the Riemann zeta function has its zeros only at the negative even integers and complex numbers with real part . Many consider it to be the most important unsolved problem in pure ...

. He is also known for advocating experimentation in mathematics, and for writing a monograph surveying his contributions on scientific computing to resolve open problems and conjectures.

Awards and honors

In 2012 he became a fellow of the

American Mathematical Society The American Mathematical Society (AMS) is an association of professional mathematicians dedicated to the interests of mathematical research and scholarship, and serves the national and international community through its publications, meetings, ...

.List of Fellows of the American Mathematical Society
, retrieved 2013-08-28.

References

External links

* * * {{DEFAULTSORT:Varga, Richard S. 1928 births 2022 deaths Numerical analysts Approximation theorists American mathematical analysts American number theorists 20th-century American mathematicians 21st-century American mathematicians Kent State University faculty Case Western Reserve University faculty Case Western Reserve University alumni Harvard Graduate School of Arts and Sciences alumni Academics from Cleveland American male sport wrestlers American people of Hungarian descent Fellows of the American Mathematical Society Fellows of the Society for Industrial and Applied Mathematics 20th-century American sportsmen

Birth and education

Career

Awards and honors

See also

References

External links