Ralph Palmer Agnew (December 29, 1900 – October 16, 1986) was an

American American(s) may refer to: * American, something of, from, or related to the United States of America, commonly known as the "United States" or "America" ** Americans, citizens and nationals of the United States of America ** American ancestry, p ...

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 ...

. Agnew was born in

Poland, Ohio Poland is a village (United States)#Ohio, village in eastern Mahoning County, Ohio, United States. The population was 2,463 at the 2020 United States census. A suburb about south of Youngstown, Ohio, Youngstown, it is part of the Mahoning Vall ...

, and did his undergraduate studies at

Allegheny College Allegheny College is a private liberal arts college in Meadville, Pennsylvania, United States. Founded in 1815, Allegheny is the oldest college in continuous existence under the same name west of the Allegheny Mountains. It is a member of the G ...

. After completing a master's degree at

Iowa State College Iowa State University of Science and Technology (Iowa State University, Iowa State, or ISU) is a public land-grant research university in Ames, Iowa, United States. Founded in 1858 as the Iowa Agricultural College and Model Farm, Iowa State be ...

he moved to

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 ...

, where he received a Ph.D. in 1930. He was appointed to the Cornell faculty in 1931. He chaired the mathematics department at Cornell from 1940 to 1950, and was responsible for bringing

William Feller William "Vilim" Feller (July 7, 1906 – January 14, 1970), born Vilibald Srećko Feller, was a Croatian–American mathematician specializing in probability theory. Early life and education Feller was born in Zagreb to Ida Oemichen-Perc, a Cro ...

and

Mark Kac Mark Kac ( ; Polish: ''Marek Kac''; August 3, 1914 – October 26, 1984) was a Polish-American mathematician. His main interest was probability theory. His question, " Can one hear the shape of a drum?" set off research into spectral theory, th ...

to Cornell. His research concerned summability of

series Series may refer to: People with the name * Caroline Series (born 1951), English mathematician, daughter of George Series * George Series (1920–1995), English physicist Arts, entertainment, and media Music * Series, the ordered sets used i ...

; he also wrote textbooks on

calculus Calculus is the mathematics, mathematical study of continuous change, in the same way that geometry is the study of shape, and algebra is the study of generalizations of arithmetic operations. Originally called infinitesimal calculus or "the ...

and differential equations. One well-known example for dealing with a system of elementary differential equations attributed to Agnew is the "snow plow problem", which is stated as:

It starts snowing in the morning and continues heavily and steadily throughout the day. A snow-plow starts plowing at noon and plows 2 miles in the first hour, and 1 mile in the second. What time did it start snowing?

The problem is deceptive for its paucity of information, and requires several common sense assumptions such as the instantaneous velocity of the plow is proportional to the depth of snow immediately in front of it, and there is no maximum or limiting velocity. These are arbitrary, but bear a particular relationship to each other. In the end, they cancel out of the equation and do not appear in the solution, which is a fixed time of day. His textbook on differential equations also contains a rather humorous note on the difficulty of converting a Laplace equation directly from Rectangular (Cartesian) coordinates to Spherical coordinates:

Doing this can make you forget your troubles the next time you have a toothache at an airport and are informed that your plane is 3 hours late.''Differential Equations'', 2nd ed., McGraw-Hill, 1960, p. 148.

References

20th-century American mathematicians Allegheny College alumni Iowa State University alumni Cornell University alumni Cornell University faculty 1900 births 1986 deaths People from Poland, Ohio {{US-mathematician-stub