Max August Zorn (; June 6, 1906 – March 9, 1993) was a German
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, structure, space, models, and change.
History
On ...
. He was an
algebraist,
group theorist, and
numerical analyst
Numerical analysis is the study of algorithms that use numerical approximation (as opposed to symbolic manipulations) for the problems of mathematical analysis (as distinguished from discrete mathematics). It is the study of numerical methods ...
. He is best known for
Zorn's lemma, a method used in
set theory
Set theory is the branch of mathematical logic that studies sets, which can be informally described as collections of objects. Although objects of any kind can be collected into a set, set theory, as a branch of mathematics, is mostly conce ...
that is applicable to a wide range of mathematical constructs such as
vector space
In mathematics and physics, a vector space (also called a linear space) is a set whose elements, often called ''vectors'', may be added together and multiplied ("scaled") by numbers called '' scalars''. Scalars are often real numbers, but can ...
s, and
ordered sets amongst others. Zorn's lemma was first postulated by
Kazimierz Kuratowski
Kazimierz Kuratowski (; 2 February 1896 – 18 June 1980) was a Polish mathematician and logician. He was one of the leading representatives of the Warsaw School of Mathematics.
Biography and studies
Kazimierz Kuratowski was born in Warsaw, (th ...
in 1922, and then independently by Zorn in 1935.
Life and career
Zorn was born in
Krefeld
Krefeld ( , ; li, Krieëvel ), also spelled Crefeld until 1925 (though the spelling was still being used in British papers throughout the Second World War), is a city in North Rhine-Westphalia, Germany. It is located northwest of Düsseldorf, i ...
,
Germany
Germany,, officially the Federal Republic of Germany, is a country in Central Europe. It is the second most populous country in Europe after Russia, and the most populous member state of the European Union. Germany is situated betwe ...
. He attended the
University of Hamburg
The University of Hamburg (german: link=no, Universität Hamburg, also referred to as UHH) is a public research university in Hamburg, Germany. It was founded on 28 March 1919 by combining the previous General Lecture System ('' Allgemeines Vor ...
. He received his
PhD in April 1930 for a thesis on
alternative algebra In abstract algebra, an alternative algebra is an algebra in which multiplication need not be associative, only alternative. That is, one must have
*x(xy) = (xx)y
*(yx)x = y(xx)
for all ''x'' and ''y'' in the algebra.
Every associative algebra is ...
s. He published his findings in ''
''. Zorn showed that
split-octonion In mathematics, the split-octonions are an 8-dimensional nonassociative algebra over the real numbers. Unlike the standard octonions, they contain non-zero elements which are non-invertible. Also the signatures of their quadratic forms differ: t ...
s could be represented by a mixed-style of matrices called
Zorn's vector-matrix algebra.
Max Zorn was appointed to an assistant position at the
University of Halle
Martin Luther University of Halle-Wittenberg (german: Martin-Luther-Universität Halle-Wittenberg), also referred to as MLU, is a public, research-oriented university in the cities of Halle and Wittenberg and the largest and oldest university i ...
. However, he did not have the opportunity to work there for long as he was forced to leave Germany in 1933 because of policies enacted by the
Nazi
Nazism ( ; german: Nazismus), the common name in English for National Socialism (german: Nationalsozialismus, ), is the far-right totalitarian political ideology and practices associated with Adolf Hitler and the Nazi Party (NSDAP) in ...
s. According to grandson Eric, "
axspoke with a raspy, airy voice most of his life. Few people knew why, because he only told the story after significant prodding, but he talked that way because pro-Hitler thugs who objected to his politics, had battered his throat in a 1933 street fight."
Zorn immigrated to the United States and was appointed a
Sterling Fellow
Sterling may refer to:
Common meanings
* Sterling silver, a grade of silver
* Sterling (currency), the currency of the United Kingdom
** Pound sterling, the primary unit of that currency
Places United Kingdom
* Stirling, a Scottish city who ...
at
Yale University
Yale University is a private research university in New Haven, Connecticut. Established in 1701 as the Collegiate School, it is the third-oldest institution of higher education in the United States and among the most prestigious in the wo ...
. While at Yale, Zorn wrote his paper "A Remark on Method in Transfinite Algebra" that stated his Maximum Principle, later called
Zorn's lemma. It requires a set that contains the union of any
chain
A chain is a serial assembly of connected pieces, called links, typically made of metal, with an overall character similar to that of a rope in that it is flexible and curved in compression but linear, rigid, and load-bearing in tension. A c ...
of
subset
In mathematics, Set (mathematics), set ''A'' is a subset of a set ''B'' if all Element (mathematics), elements of ''A'' are also elements of ''B''; ''B'' is then a superset of ''A''. It is possible for ''A'' and ''B'' to be equal; if they are ...
s to have one chain not contained in any other, called the
maximal element
In mathematics, especially in order theory, a maximal element of a subset ''S'' of some preordered set is an element of ''S'' that is not smaller than any other element in ''S''. A minimal element of a subset ''S'' of some preordered set is defin ...
. He illustrated the principle with applications in ring theory and field extensions. Zorn's lemma is an alternative expression of the
axiom of choice
In mathematics, the axiom of choice, or AC, is an axiom of set theory equivalent to the statement that ''a Cartesian product of a collection of non-empty sets is non-empty''. Informally put, the axiom of choice says that given any collectio ...
, and thus a subject of interest in
axiomatic set theory
Set theory is the branch of mathematical logic that studies Set (mathematics), sets, which can be informally described as collections of objects. Although objects of any kind can be collected into a set, set theory, as a branch of mathematics, ...
.
In 1936 he moved to
UCLA
The University of California, Los Angeles (UCLA) is a public land-grant research university in Los Angeles, California. UCLA's academic roots were established in 1881 as a teachers college then known as the southern branch of the California St ...
and remained until 1946. While at UCLA Zorn revisited his study of alternative rings and proved the existence of the
nilradical of certain
alternative ring In abstract algebra, an alternative algebra is an algebra in which multiplication need not be associative, only alternative. That is, one must have
*x(xy) = (xx)y
*(yx)x = y(xx)
for all ''x'' and ''y'' in the algebra.
Every associative algebra is o ...
s. According to
Angus E. Taylor
Angus Ellis Taylor (October 13, 1911 – April 6, 1999) was a mathematician and professor at various universities in the University of California system. He earned his undergraduate degree at Harvard ''summa cum laude'' in 1933 and his PhD at C ...
, Max was his most stimulating colleague at UCLA.
In 1946 Zorn became a professor at
Indiana University
Indiana University (IU) is a system of public universities in the U.S. state of Indiana.
Campuses
Indiana University has two core campuses, five regional campuses, and two regional centers under the administration of IUPUI.
*Indiana Universit ...
, where he taught until retiring in 1971. He was thesis advisor for
Israel Nathan Herstein
Israel Nathan Herstein (March 28, 1923 – February 9, 1988) was a mathematician, appointed as professor at the University of Chicago in 1951. He worked on a variety of areas of algebra, including ring theory, with over 100 research papers and ov ...
.
Zorn died in
Bloomington, Indiana
Bloomington is a city in and the county seat of Monroe County, Indiana, Monroe County in the central region of the U.S. state of Indiana. It is the List of municipalities in Indiana, seventh-largest city in Indiana and the fourth-largest outside ...
, in March 1993, of congestive heart failure, according to his obituary in ''
The New York Times
''The New York Times'' (''the Times'', ''NYT'', or the Gray Lady) is a daily newspaper based in New York City with a worldwide readership reported in 2020 to comprise a declining 840,000 paid print subscribers, and a growing 6 million paid ...
''.
Family
Max Zorn married Alice Schlottau and they had one son, Jens, and one daughter, Liz. Jens (born June 19, 1931) is an emeritus professor of physics at the
University of Michigan
, mottoeng = "Arts, Knowledge, Truth"
, former_names = Catholepistemiad, or University of Michigania (1817–1821)
, budget = $10.3 billion (2021)
, endowment = $17 billion (2021)As o ...
and an accomplished sculptor. Max Zorn's grandson
Eric Zorn
Eric Zorn (born January 6, 1958) is a former American op-ed columnist and daily blogger for the ''Chicago Tribune'' who specialized in local news as well as politics.
Early life and education
Zorn is a graduate of the University of Michigan, wher ...
was a columnist for the ''
Chicago Tribune
The ''Chicago Tribune'' is a daily newspaper based in Chicago, Illinois, United States, owned by Tribune Publishing. Founded in 1847, and formerly self-styled as the "World's Greatest Newspaper" (a slogan for which WGN radio and television ar ...
'' from 1986 until 2021; after retirement
Eric Zorn
Eric Zorn (born January 6, 1958) is a former American op-ed columnist and daily blogger for the ''Chicago Tribune'' who specialized in local news as well as politics.
Early life and education
Zorn is a graduate of the University of Michigan, wher ...
started a Substack newsletter titled "The Picayune Sentinel", named after the mathematics newsletter that Max Zorn had distributed during his years at Indiana University. Max's great grandson, Alexander Wolken Zorn, received a PhD in mathematics from the University of California Berkeley in 2018.
See also
*
Artin–Zorn theorem In mathematics, the Artin–Zorn theorem, named after Emil Artin and Max Zorn, states that any finite alternative division ring is necessarily a finite field. It was first published in 1930 by Zorn, but in his publication Zorn credited it to Arti ...
*
Zorn ring In mathematics, a Zorn ring is an alternative ring in which for every non-nilpotent ''x'' there exists an element ''y'' such that ''xy'' is a non-zero idempotent . named them after Max August Zorn, who studied a similar condition in .
For associa ...
References
* Steve Carlson (2009
Max Zorn: World Renowned Mathematician and Member Indiana MAA Section, from
Mathematics Association of America
The Mathematical Association of America (MAA) is a professional society that focuses on mathematics accessible at the undergraduate level. Members include university, college, and high school teachers; graduate and undergraduate students; pure a ...
.
* Darrell Haile (1993
On Max Zorn's Contributions to Mathematics(includes John Ewing, "Zorn's Lemma"), from Memorial Conference at Indiana University, June 1993.
External links
*
*
{{DEFAULTSORT:Zorn, Max August
20th-century American mathematicians
20th-century German mathematicians
Set theorists
Algebraists
Numerical analysts
Indiana University faculty
German emigrants to the United States
1906 births
1993 deaths
People from Krefeld
Deaths from congestive heart failure
University of Hamburg alumni
University of California, Los Angeles faculty
Yale University fellows