Kenneth Appel
Kenneth Ira Appel | |
|---|---|
| Born | October 8, 1932 |
| Citizenship | American |
| Alma mater | B.S. - Queens College, City University of New York Doctor of Philosophy - University of Michigan |
| Known for | Proving the Four-color theorem with Wolfgang Haken |
| Awards | Fulkerson Prize [1979] |
| Scientific career | |
| Fields | Graph theory, Combinatorics |
| Institutions | University of Illinois at Urbana-Champaign, University of New Hampshire |
| Doctoral advisor | Roger Lyndon |
Kenneth Ira Appel (born October 8, 1932 in Brooklyn, New York) is a mathematician who in 1976, with colleague Wolfgang Haken at the University of Illinois at Urbana-Champaign, solved one of the most famous problems in mathematics, the four-color theorem. They proved that any two-dimensional map, with certain limitations, can be filled in with four colors without any adjacent "countries" sharing the same color.
The proof has been one of the most controversial of modern mathematics because of its heavy dependence on computer "number-crunching" to sort through possibilities, which drew criticism from many in the mathematical community for its inelegance: "a good mathematical proof is like a poem — this is a telephone directory!" [1] Appel and Haken agreed in a 1977 interview that it was not "elegant, concise and completely comprehensible by a human mathematical mind". [2]
However, the proof was the start of a sea-change in mathematicians' attitudes toward computers – which they had largely disdained as a tool for engineers rather than for theoreticians - leading to the creation of what is sometimes called "experimental mathematics".
Appel studied at Queens College and the University of Michigan, followed by research at the Institute for Defense Analysis in Princeton before he became a faculty member at the University of Illinois at Urbana-Champaign in 1961.
From 1993 through 2002, Appel was chair of the mathematics department at the University of New Hampshire in Durham, New Hampshire.[3] Although retired now, he still works and occasionally teaches there and has an office on campus. As emeritus faculty Appel works with local schools in implementing and maintaining WeBWorK, a web-based open source mathematics-assignment system developed at the University of Rochester.