Harold Varner McIntosh (1929–2015) was an American computational physicist who worked for many years in Mexico. Beyond physics, his research interests included

quantum chemistry Quantum chemistry, also called molecular quantum mechanics, is a branch of physical chemistry focused on the application of quantum mechanics to chemical systems, particularly towards the quantum-mechanical calculation of electronic contributions ...

programming language A programming language is a system of notation for writing computer programs. Programming languages are described in terms of their Syntax (programming languages), syntax (form) and semantics (computer science), semantics (meaning), usually def ...

design,

cellular automata A cellular automaton (pl. cellular automata, abbrev. CA) is a discrete model of computation studied in automata theory. Cellular automata are also called cellular spaces, tessellation automata, homogeneous structures, cellular structures, tessel ...

, and

flexagon In geometry, flexagons are Plane (geometry), flat models, usually constructed by folding strips of paper, that can be ''flexed'' or folded in certain ways to reveal faces besides the two that were originally on the back and front. Flexagons are ...

Early life and education

McIntosh was born on March 11, 1929, in Colorado, and was an undergraduate at the Colorado State College of Agriculture and Mechanic Arts (now

Colorado State University Colorado State University (Colorado State or CSU) is a Public university, public Land-grant university, land-grant research university in Fort Collins, Colorado, United States. It is the flagship university of the Colorado State University Syst ...

), where he graduated in 1949 with a degree in physics. He went on to graduate study at

Cornell University Cornell University is a Private university, private Ivy League research university based in Ithaca, New York, United States. The university was co-founded by American philanthropist Ezra Cornell and historian and educator Andrew Dickson W ...

, earning a master's degree in 1952. He began doctoral study at

Brandeis University Brandeis University () is a Private university, private research university in Waltham, Massachusetts, United States. It is located within the Greater Boston area. Founded in 1948 as a nonsectarian, non-sectarian, coeducational university, Bra ...

, but stopped before completing the program. Much later in his career, he completed a doctorate in quantum chemistry at

Uppsala University Uppsala University (UU) () is a public university, public research university in Uppsala, Sweden. Founded in 1477, it is the List of universities in Sweden, oldest university in Sweden and the Nordic countries still in operation. Initially fou ...

in Sweden in 1972.

Career and later life

After leaving Brandeis, McIntosh worked at the

Aberdeen Proving Ground Aberdeen Proving Ground (APG) is a U.S. Army facility located adjacent to Aberdeen, Harford County, Maryland, United States. More than 7,500 civilians and 5,000 military personnel work at APG. There are 11 major commands among the tenant units, ...

, and then in the

Research Institute for Advanced Studies The Baltimore-based Research Institute for Advanced Studies (RIAS), not to be confused with the better-known Institute for Advanced Study in Princeton, New Jersey, was among the several centers for research in the mathematical and physical sciences ...

Baltimore Baltimore is the most populous city in the U.S. state of Maryland. With a population of 585,708 at the 2020 census and estimated at 568,271 in 2024, it is the 30th-most populous U.S. city. The Baltimore metropolitan area is the 20th-large ...

. In 1962 he moved to the

University of Florida The University of Florida (Florida or UF) is a public university, public land-grant university, land-grant research university in Gainesville, Florida, United States. It is a senior member of the State University System of Florida and a preem ...

to work on quantum theory in the department of physics and astronomy there. In 1964, McIntosh moved to Mexico, where he would work for the rest of his career. He started in the center for research and advanced studies of the

Instituto Politécnico Nacional The National Polytechnic Institute (), abbreviated IPN, is one of the largest public universities in Mexico with 171,581 students at the high school, undergraduate and postgraduate levels. It is the second-best university in Mexico in the techni ...

, which eventually became

CINVESTAV The Center for Research and Advanced Studies of the National Polytechnic Institute (in Spanish: ''Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional'' or simply as ''CINVESTAV-IPN'') is a Mexican non-government ...

; he worked there on the design of the CONVERT programming language. After another year as director of programming at the computer center of the

National Autonomous University of Mexico The National Autonomous University of Mexico (, UNAM) is a public university, public research university in Mexico. It has several campuses in Mexico City, and many others in various locations across Mexico, as well as a presence in nine countri ...

(again working on programming language design) he returned in 1966 to the Instituto Politécnico Nacional as a professor in the School of Physics and Mathematics and coordinator for applied mathematics. Here, as well as the development of programming languages and software for scientific visualization, his interests returned to physics, including issues of degeneracy in the solution of physical equations, and quantum two-body problems involving a

magnetic monopole In particle physics, a magnetic monopole is a hypothetical particle that is an isolated magnet with only one magnetic pole (a north pole without a south pole or vice versa). A magnetic monopole would have a net north or south "magnetic charge". ...

(the so-called MICZ Kepler system, in which the M stands for McIntosh). After nine years at the Instituto Politécnico Nacional, McIntosh moved in 1975 to the Institute of Sciences of the

Meritorious Autonomous University of Puebla The Meritorious Autonomous University of Puebla () (BUAP) is the oldest and largest university in Puebla, Mexico. Founded on 15 April 1578 as Colegio del Espíritu Santo, the school was sponsored by the Society of Jesus during most of the Spanis ...

, where he became the founding director of the Department of Microcomputer Applications. There, his interests shifted to

for the final decades of his career. He died in Puebla, Mexico on November 30, 2015.

Recognition

McIntosh was a member of the

Mexican Academy of Sciences The Mexican Academy of Sciences ''(Academia Mexicana de Ciencias)'' is a non-profit organization comprising over 1800 distinguished Mexico, Mexican scientists, attached to various institutions in the country, as well as a number of eminent forei ...

. In 2008, a special issue of the ''Journal of Cellular Automata'' was published in his honor.

Selected publications

* * * * * * * *

References

External links

Home page
{{DEFAULTSORT:McIntosh, Harold V. 1929 births 2015 deaths American physicists Programming language designers Cellular automatists Colorado State University alumni Cornell University alumni Uppsala University alumni Academic staff of the Instituto Politécnico Nacional Academic staff of the Meritorious Autonomous University of Puebla Members of the Mexican Academy of Sciences