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 matrices. ...

. He was an Emeritus University Professor of Mathematical Sciences at

Kent State University Kent State University (KSU) is a public research university in Kent, Ohio. The university also includes seven regional campuses in Northeast Ohio and additional facilities in the region and internationally. Regional campuses are located in As ...

and an adjunct Professor at

Case Western Reserve University Case Western Reserve University (CWRU) is a private research university in Cleveland, Ohio. Case Western Reserve was established in 1967, when Western Reserve University, founded in 1826 and named for its location in the Connecticut Western Reser ...

. 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 mul ...

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

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 or scientific computation (SC), is a field in mathematics that uses advanced computing capabilities to understand and solve complex problems. It is an area of science that spans many disc ...

. 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 ( ), officially the City of Cleveland, is a city in the U.S. state of Ohio and the county seat of Cuyahoga County. Located in the northeastern part of the state, it is situated along the southern shore of Lake Erie, across the U.S. ...

Ohio Ohio () is a state in the Midwestern region of the United States. Of the fifty U.S. states, it is the 34th-largest by area, and with a population of nearly 11.8 million, is the seventh-most populous and tenth-most densely populated. The sta ...

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 (also known as folkstyle wrestling) is the form of wrestling practiced at the college and university level in the United States. This style of wrestling, with some slight modifications, is also practiced at high school and mi ...

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

Harvard University Harvard University is a private Ivy League research university in Cambridge, Massachusetts. Founded in 1636 as Harvard College and named for its first benefactor, the Puritan clergyman John Harvard, it is the oldest institution of higher le ...

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–Szegő ...

, 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 an ...

s. Varga received his Ph.D. 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 (mathematics), function that is holomorphic function, holomorphic on the whole complex plane. Typical examples of entire functions are polynomia ...

and their Respective

Partial Sums In mathematics, a series is, roughly speaking, a description of the operation of adding infinitely many quantities, one after the other, to a given starting quantity. The study of series is a major part of calculus and its generalization, math ...

''. 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 Geo ...

, 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 ''n''-th approximation is derived fr ...

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 \mathop(A), \la ...

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 research university in Cleveland, Ohio. Case Western Reserve was established in 1967, when Western Reserve University, founded in 1826 and named for its location in the Connecticut Western Res ...

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 mathematics. ...

, 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 ...

. 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 Mathematical analysts 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 People 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

Birth and education

Career

Awards and honors

See also

References

External links