Ivan Rival (March 15, 1947 – January 22, 2002 in

Ottawa Ottawa is the capital city of Canada. It is located in the southern Ontario, southern portion of the province of Ontario, at the confluence of the Ottawa River and the Rideau River. Ottawa borders Gatineau, Gatineau, Quebec, and forms the cor ...

Ontario Ontario is the southernmost Provinces and territories of Canada, province of Canada. Located in Central Canada, Ontario is the Population of Canada by province and territory, country's most populous province. As of the 2021 Canadian census, it ...

, Canada) was a Canadian

mathematician A mathematician is someone who uses an extensive knowledge of mathematics in their work, typically to solve mathematical problems. Mathematicians are concerned with numbers, data, quantity, mathematical structure, structure, space, Mathematica ...

and

computer scientist A computer scientist is a scientist who specializes in the academic study of computer science. Computer scientists typically work on the theoretical side of computation. Although computer scientists can also focus their work and research on ...

, a professor of mathematics at the

University of Calgary {{Infobox university , name = University of Calgary , image = University of Calgary coat of arms without motto scroll.svg , image_size = 150px , caption = Coat of arms , former ...

and of computer science at the

University of Ottawa The University of Ottawa (), often referred to as uOttawa or U of O, is a Official bilingualism in Canada, bilingual public research university in Ottawa, Ontario, Canada. The main campus is located on directly to the northeast of Downtown Ot ...

.... Rival's Ph.D. thesis concerned

lattice theory A lattice is an abstract structure studied in the mathematical subdisciplines of order theory and abstract algebra. It consists of a partially ordered set in which every pair of elements has a unique supremum (also called a least upper bou ...

. After moving to Calgary he began to work more generally with

partially ordered set In mathematics, especially order theory, a partial order on a Set (mathematics), set is an arrangement such that, for certain pairs of elements, one precedes the other. The word ''partial'' is used to indicate that not every pair of elements need ...

s, and to study

fixed point theorem In mathematics, a fixed-point theorem is a result saying that a function ''F'' will have at least one fixed point (a point ''x'' for which ''F''(''x'') = ''x''), under some conditions on ''F'' that can be stated in general terms. In mathematical ...

s for partially ordered structures. He was a frequent organizer of conferences in

order theory Order theory is a branch of mathematics that investigates the intuitive notion of order using binary relations. It provides a formal framework for describing statements such as "this is less than that" or "this precedes that". This article intr ...

, and in 1984 he founded the journal ''

Order Order, ORDER or Orders may refer to: * A socio-political or established or existing order, e.g. World order, Ancien Regime, Pax Britannica * Categorization, the process in which ideas and objects are recognized, differentiated, and understood ...

''. As a computer scientist at Ottawa, he shifted research topics, applying his expertise in order theory to the study of

data structure In computer science, a data structure is a data organization and storage format that is usually chosen for Efficiency, efficient Data access, access to data. More precisely, a data structure is a collection of data values, the relationships amo ...

s, computational geometry, and

graph drawing Graph drawing is an area of mathematics and computer science combining methods from geometric graph theory and information visualization to derive two-dimensional depictions of graph (discrete mathematics), graphs arising from applications such ...

. Rival grew up in

Hamilton, Ontario Hamilton is a port city in the Canadian Provinces and territories of Canada, province of Ontario. Hamilton has a 2021 Canadian census, population of 569,353 (2021), and its Census Metropolitan Area, census metropolitan area, which encompasses ...

. He earned a bachelor's degree at

McMaster University McMaster University (McMaster or Mac) is a public research university in Hamilton, Ontario, Canada. The main McMaster campus is on of land near the residential neighbourhoods of Ainslie Wood, Ontario, Ainslie Wood and Westdale, Ontario, Westd ...

in 1969, and received his Ph.D. from the

University of Manitoba The University of Manitoba (U of M, UManitoba, or UM) is a public research university in Winnipeg, Manitoba, Canada. Founded in 1877, it is the first university of Western Canada. Both by total student enrolment and campus area, the University of ...

in 1974 under the supervision of George Gratzer.. After postdoctoral stints visiting Robert Dilworth at

Caltech The California Institute of Technology (branded as Caltech) is a private university, private research university in Pasadena, California, United States. The university is responsible for many modern scientific advancements and is among a small g ...

and

Rudolf Wille Rudolf Wille (2 November 1937 – 22 January 2017) was a German mathematician and was professor of General Algebra from 1970 to 2003 at Technische Universität Darmstadt (TU Darmstadt). His most celebrated work is the invention of formal concept ...

at the Technische Hochschule Darmstadt, he took a faculty position at Calgary in 1975, and was promoted to full professor in 1981. In 1986, he moved to the University of Ottawa, where he became chair of the computer science department. Rival's doctoral students included Dwight Duffus, the Goodrich C. White Professor of Mathematics & Computer Science at

Emory University Emory University is a private university, private research university in Atlanta, Georgia, United States. It was founded in 1836 as Emory College by the Methodist Episcopal Church and named in honor of Methodist bishop John Emory. Its main campu ...

. Duffus took over the editorship of ''Order'' after the retirement (as editor) of

William T. Trotter William Thomas Trotter Jr. is an American mathematician, who is on the faculty of the Department of Mathematics at the Georgia Institute of Technology. His main expertise is partially ordered sets, but he has also done significant work in other are ...

, who took over the editorship from Rival.Publisher web site for ''Order''
retrieved 2010-09-10.

References

External links

The Ivan Rival Memorial Website
{{DEFAULTSORT:Rival, Ivan 1947 births 2002 deaths Canadian mathematicians Academics from Hamilton, Ontario McMaster University alumni University of Manitoba alumni Academic staff of the University of Calgary Lattice theorists Researchers in geometric algorithms Academic staff of Technische Universität Darmstadt