Jeff Kahn

Jeffry " Jeff" Ned Kahn ( born 1950 ) is an American mathematician who deals with combinatorics.

Kahn received his doctorate in 1979 at the Ohio State University in DK Ray - Chaudhuri (finite inversive planes with bundle theorem ). He is a professor at Rutgers University.

In 1993, he refuted with Gil Kalai the Borsuk 's conjecture. In 1980 he proved a long open conjecture in the geometry of Möbius levels ( characterized them, those in which the tufts rate applies, as ovoid -like). He also deals with the theory of phase transitions, for example, in the model of hard spheres on grids ( where in 2004 he proved the existence of a phase transition with David Galvin ).

In 1996 he was awarded with David Reimer the George Pólya Prize. Kahn proved with Michael Saks and Cliff Smyth a dual version of Reimer 's inequality (previously conjecture of van den Berg and Harry Kesten ) and thus a combinatorial conjecture of Rudich that has applications in cryptographic complexity. In 1994 he was invited speaker at the International Congress of Mathematicians in Zurich ( Asymptotics of hypergraph matching, covering and coloring problems ). In 2012 he was awarded the Fulkerson Prize.