Marie Ennemond Camille Jordan (January 5, 1838 – January 22, 1922) was a French mathematician, known both for his foundational work in group theory and for his influential Cours d'analyse. He was born in Lyons and educated at the École polytechnique. He was an engineer by profession; later in life he taught at the École polytechnique and the Collège de France; where he had a reputation for eccentric choices of notation. January 5 is the 5th day of the year in the Gregorian Calendar. ... 1838 was a common year starting on Monday (see link for calendar). ... January 22 is the 22nd day of the year in the Gregorian Calendar. ... 1922 was a common year starting on Sunday (see link for calendar). ... A mathematician is a person whose area of study and research is mathematics. ... Group theory is that branch of mathematics concerned with the study of groups. ... Lyons), see Lyons (disambiguation). ... The cadets of Polytechnique rushed to the defense of Paris against the foreign armies in 1814. ... The Collège de France is a higher education teaching and research establishment located in Paris, France. ...

He is remembered now by name in a number of foundational results:

• the Jordan curve theorem, a topological result required in complex analysis;
• the Jordan normal form in linear algebra;
• in mathematical analysis, Jordan content is an area measure that predates measure theory;
• in group theory the Jordan-Hölder theorem on composition series is a basic result.

Jordan's work did much to bring Galois theory into the mainstream. He also investigated the Mathieu groups, the first examples of sporadic groups. His Traité des substitutions, on permutation groups, was published in 1870. In topology, the Jordan curve theorem states that every non-self-intersecting loop in the plane divides the plane into an inside and an outside. The precise mathematical statement is as follows. ... Complex analysis is the branch of mathematics investigating holomorphic functions, i. ... In linear algebra, the Jordan normal form, also called the Jordan canonical form, named in honor of the 19th and early 20th-century French mathematician Camille Jordan, answers the question, for a given square matrix M over a field K, to what extent M can be simplified into a standard... Linear algebra is the branch of mathematics concerned with the study of vectors, vector spaces (or linear spaces), linear transformations, and systems of linear equations. ... Analysis is that branch of mathematics which deals with the real numbers, complex numbers, and their functions. ... In mathematics, a measure is a function that assigns a number, e. ... Group theory is that branch of mathematics concerned with the study of groups. ... In mathematics, a composition series of a group G is a normal series such that each Hi is a maximal normal subgroup of Hi+1. ... In mathematics, a composition series of a group G is a chain of subgroups of G satisfying where stands for normal subgroup, such that each quotient group Hi+1/Hi is a simple group. ... In mathematics, Galois theory is that branch of abstract algebra which studies the symmetries of the roots of polynomials. ... In mathematics, the Mathieu groups are five finite simple groups discovered by the French mathematician Emile Léonard Mathieu. ... The classification of the finite simple groups is a vast body of work in mathematics, mostly published between around 1955 and 1983, which is thought to classify all of the finite simple groups. ... In mathematics, a permutation group is a group G whose elements are permutations of a given set M, and whose operation is the composition of permutations in G (which are thought of as bijective functions from the set M to itself); the relationship is often written as (G,M). ... 1870 was a common year starting on Saturday (see link for calendar). ...

The asteroid 25593 Camillejordan is named in his honour. An asteroid is a small, solid object in our Solar System, orbiting the Sun. ...

Camille Jordan is not to be confused with the German mathematician Wilhelm Jordan (1842-1899). A mathematician is a person whose area of study and research is mathematics. ... Wilhelm Jordan (1842 – 1899) is remembered for the Gauss-Jordan elimination algorithm, with Jordan improving the stability of the algorithm so it could be applied to minimizing the squared error in surveying. ... 1842 was a common year starting on Saturday (see link for calendar). ... 1899 was a common year starting on Sunday (see link for calendar). ...

External link

• Biography (http://www-groups.dcs.st-and.ac.uk/~history/Mathematicians/Jordan.html) at the MacTutor archive