Hubert Stanley Wall (December 2, 1902 – September 12, 1971) was an American

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 ...

who worked primarily in the field of

continued fraction A continued fraction is a mathematical expression that can be written as a fraction with a denominator that is a sum that contains another simple or continued fraction. Depending on whether this iteration terminates with a simple fraction or not, ...

s. He is also known as one of the leading proponents of the

Moore method The Moore method is a deductive manner of instruction used in advanced mathematics courses. It is named after Robert Lee Moore, a famous topologist who first used a stronger version of the method at the University of Pennsylvania The ...

of teaching.

Early life and education

Wall was born in

Rockwell City, Iowa Rockwell City is a city and the county seat of Calhoun County, Iowa, United States. The population was 2,240 in 2020.

on December 2, 1902. He received the

Bachelor of Arts A Bachelor of Arts (abbreviated B.A., BA, A.B. or AB; from the Latin ', ', or ') is the holder of a bachelor's degree awarded for an undergraduate program in the liberal arts, or, in some cases, other disciplines. A Bachelor of Arts deg ...

and

Master of Arts A Master of Arts ( or ''Artium Magister''; abbreviated MA or AM) is the holder of a master's degree awarded by universities in many countries. The degree is usually contrasted with that of Master of Science. Those admitted to the degree have ...

degrees from

Cornell College Cornell College is a private liberal arts college in Mount Vernon, Iowa. Originally the Iowa Conference Seminary (Methodist), the school was founded in 1853 by George Bryant Bowman. Four years later, in 1857, the name was changed to Cornell Co ...

Mount Vernon, Iowa Mount Vernon is a city in Linn County, Iowa, United States, adjacent to the city of Lisbon. The population was 4,527 at the time of the 2020 census. Mount Vernon is part of the Cedar Rapids Metropolitan Statistical Area. History Mount Verno ...

in 1924. He 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 from the University of Wisconsin (now

University of Wisconsin–Madison The University of Wisconsin–Madison (University of Wisconsin, Wisconsin, UW, UW–Madison, or simply Madison) is a public land-grant research university in Madison, Wisconsin, United States. It was founded in 1848 when Wisconsin achieved st ...

) in 1927. He married Mary Kate Parker, a lawyer and Texas assistant Attorney General. Her specialty was election law.

Career

Upon receiving his

Wall joined the faculty at

Northwestern University Northwestern University (NU) is a Private university, private research university in Evanston, Illinois, United States. Established in 1851 to serve the historic Northwest Territory, it is the oldest University charter, chartered university in ...

and stayed until 1944 except for the academic year 1938–1939 when he was at the

Institute for Advanced Study The Institute for Advanced Study (IAS) is an independent center for theoretical research and intellectual inquiry located in Princeton, New Jersey. It has served as the academic home of internationally preeminent scholars, including Albert Ein ...

. He then went to the

Illinois Institute of Technology The Illinois Institute of Technology, commonly referred to as Illinois Tech and IIT, is a Private university, private research university in Chicago, Illinois, United States. Tracing its history to 1890, the present name was adopted upon the m ...

for two years before moving in 1946 to the

University of Texas The University of Texas at Austin (UT Austin, UT, or Texas) is a public research university in Austin, Texas, United States. Founded in 1883, it is the flagship institution of the University of Texas System. With 53,082 students as of fall 2 ...

where he spent the rest of his career. He became an

emeritus professor ''Emeritus/Emerita'' () is an honorary title granted to someone who retires from a position of distinction, most commonly an academic faculty position, but is allowed to continue using the previous title, as in "professor emeritus". In some c ...

in 1970. Most of Wall's mathematical research was in various aspects of the analytic theory of

continued fractions A continued fraction is a mathematical expression that can be written as a fraction with a denominator that is a sum that contains another simple or continued fraction. Depending on whether this iteration terminates with a simple fraction or no ...

. This included the theory of positive-definite continued fractions, convergence results for continued fractions, parabola theorems, Hausdorff moments, and Hausdorff summability. He studied the polynomials now named Wall polynomials after him. While at Northwestern he started a collaboration with

Ernst Hellinger Ernst David Hellinger (September 30, 1883 – March 28, 1950) was a German mathematician and is primarily known for his works on statistics and probability. His works include Hellinger distance and Hellinger integral which were introduced by him ...

, and he was very interested in

Hellinger integral In mathematics, the Hellinger integral is an integral introduced by that is a special case of the Kolmogorov integral. It is used to define the Hellinger distance In probability and statistics, the Hellinger distance (closely related to, althoug ...

s throughout his career, but did publish anything on them. While at Texas Wall was a prominent practitioner of the

of teaching. John Parker wrote, "Wall had long ago thrown himself wholeheartedly into the Moore tradition, with his own interpretation of the Moore method, and there was a good deal of cross pollination of students through their courses, some steered to the PhD by Moore and others by Wall and yman J.Ettlinger. Between them, they continued to dominate PhD guidance in Pure Mathematics throughout the 1950s and 1960s." The University of Texas memorial to Wall suggests that he may have picked up some of these ideas at Northwestern from Van Vleck and

Hellinger Hellinger is a surname. Notable people with the surname include: *Ernst Hellinger (1883–1950), German mathematician **Hellinger distance, used to quantify the similarity between two probability distributions ** Hellinger integral, used to define ...

and says, "Since there were already people on the Texas faculty who had used innovative techniques (chiefly

Robert Lee Moore Robert Lee Moore (November 14, 1882 – October 4, 1974) was an American mathematician who taught for many years at the University of Texas. He is known for his work in general topology, for the Moore method of teaching university mathematics, ...

and some of his colleagues), Wall tried their methods. For him and for his students it was an unqualified success." Wall had 66 doctoral students, 61 at the University of Texas. Wall died in

Austin Austin refers to: Common meanings * Austin, Texas, United States, a city * Austin (given name), a list of people and fictional characters * Austin (surname), a list of people and fictional characters * Austin Motor Company, a British car manufac ...

on September 12, 1971.

Selected publications

* *

Notes

External links

* {{DEFAULTSORT:Wall, Hubert Stanley 1902 births 1971 deaths People from Calhoun County, Iowa 20th-century American mathematicians American mathematical analysts Institute for Advanced Study visiting scholars Illinois Institute of Technology faculty Northwestern University faculty University of Wisconsin–Madison alumni University of Texas at Austin faculty