In
mathematics, the
Hodge conjecture is a major unsolved problem in the field of
algebraic geometry that relates the
algebraic topology of a
non-singular complex algebraic variety and the subvarieties of that variety. More specifically, the conjecture says that certain
de Rham cohomology classes are algebraic, that is, they are sums of
Poincaré duals of the
homology classes of subvarieties. It was formulated by the Scottish mathematician
William Vallance Douglas Hodge as a result of a work in between 1930 and 1940 to enrich the description of de Rham cohomology to include extra structure that is present in the case of complex algebraic varieties. It received little attention before Hodge presented it in an address during the 1950
International Congress of Mathematicians, held in Cambridge,
Massachusetts, U.S. The Hodge conjecture is one of the
Clay Mathematics Institute's
Millennium Prize Problems, with a prize of $1,000,000 for whoever can prove or disprove the Hodge conjecture.