Paul Gordan(1837 — 1912)

Paul Gordan

royaume de Prusse

6 min read

SciencesMathématicien(ne)19th Century19th-century Germany, the golden age of German mathematics (Königsberg, Erlangen)

Paul Gordan was a 19th-century German mathematician, famous for his work on invariant theory. Nicknamed the “king of invariant theory,” he left his mark on algebra through his mastery of calculations.

Frequently asked questions

Paul Gordan (1837-1912) was a German mathematician renowned for his exceptional mastery of algebraic calculations. The key thing to remember is that he earned this nickname by proving in 1868 that every binary form possesses a finite system of basic invariants – a result so difficult that it was long known as "Gordan's theorem." Unlike the abstract approach that followed, Gordan excelled at symbolic calculations of dizzying length, which few of his contemporaries dared to tackle.

Famous Quotes

« This is not mathematics, this is theology. »

Key Facts

  • Born in 1837 in Breslau (present-day Wrocław), died in 1912 in Erlangen
  • Professor of mathematics at the University of Erlangen from 1875
  • A recognized specialist in invariant theory, nicknamed the “king of invariants”
  • Author in 1868 of a major theorem on binary forms (Gordan's theorem)
  • Reacted in 1888 to David Hilbert's non-constructive existence proof with his now-famous remark about “theology”

Works & Achievements

Gordan's theorem (finiteness of invariants of binary forms) (1868)

Proof that every binary form possesses a finite system of base invariants and covariants. A major result that earned him the nickname “the king of invariant theory.”

Clebsch-Gordan coefficients (1866-1875)

Arising from his work with Clebsch, these coefficients are today essential in quantum physics for combining angular momenta.

Theorie der Abel'schen Functionen (with A. Clebsch) (1866)

A foundational treatise on abelian functions that cemented the reputation of both authors.

Vorlesungen über Invariantentheorie (1885-1887)

A definitive two-volume course methodically setting out the symbolic techniques of invariant theory.

Gordan's lemma (1873)

A result on the integer solutions of systems of linear inequalities, still used in convex geometry and optimization.

Supervision of Emmy Noether's doctoral thesis (1907)

Supervision of **Emmy Noether**'s doctoral thesis at Erlangen, an indirect but decisive contribution to the birth of modern algebra.

Anecdotes

When the young David Hilbert proved the « finite basis theorem » in 1888 using an abstract method, without explicitly computing the invariants, Paul Gordan is said to have exclaimed: “This is not mathematics, it is theology!” This quip has remained famous as a symbol of the clash between the old computational school and the new abstract mathematics.

Gordan was nicknamed “the king of invariant theory” because of his virtuosity in algebraic calculations of dizzying length, which few mathematicians dared to tackle. It is said that he thought while pacing back and forth and speaking aloud, rather than by writing.

In 1868, Gordan managed to prove that binary forms possess only a finite number of basic invariants — a result so difficult that it was long called the “Gordan theorem”. Twenty years later, Hilbert generalized it in one stroke, rendering Gordan's proof almost obsolete.

Paul Gordan was the thesis advisor of Emmy Noether, one of the greatest mathematicians in history, who defended her thesis at Erlangen in 1907. An irony of history: Noether later abandoned her teacher's computational style to become a pioneer of abstract algebra — the very thing Gordan deemed “theological”.

Despite his initial skepticism, Gordan eventually came to recognize the value of Hilbert's ideas. He is said to have later admitted, with humor, that “even theology has its merits”, showing that a great scholar can change his mind when faced with a new idea.

Primary Sources

Beweis, dass jede Covariante und Invariante einer binären Form eine ganze Function mit numerischen Coefficienten einer endlichen Anzahl solcher Formen ist (1868)
Here Gordan establishes that every covariant and every invariant of a binary form can be expressed as an integral function of a finite number of fundamental forms — the so-called “Gordan's theorem.”
Vorlesungen über Invariantentheorie (Lectures on Invariant Theory), edited by Georg Kerschensteiner (1885-1887)
A landmark two-volume treatise setting out the symbolic methods for computing invariants, the fruit of Gordan's teaching at Erlangen.
Theorie der Abel'schen Functionen (with Alfred Clebsch) (1866)
A joint work in which Clebsch and Gordan develop the theory of Abelian functions, illustrating their fruitful collaboration.
Über das Formensystem binärer Formen (1875)
A memoir systematizing the complete system of binary forms, the high point of the computational method that Gordan brought to perfection.

Key Places

Breslau (Wrocław)

City in Silesia where Paul Gordan was born in 1837 and where he earned his doctorate in 1862. A major university center of eastern Prussia.

University of Erlangen

University in Bavaria where Gordan was a professor from 1874 to 1910 and supervised Emmy Noether's thesis. The hub of his scientific influence.

Giessen

City in Hesse where Gordan joined Alfred Clebsch and where their collaboration on invariants and abelian functions began.

Königsberg

Birthplace of a great German mathematical school (heir to Jacobi) where Gordan trained in algebra and analysis.

Berlin

The Prussian capital and a major mathematical center of the 19th century, where Gordan completed his training under the masters of the era.

See also