McKay conjecture

In mathematics, specifically in the field of group theory, the McKay conjecture is a theorem of equality between two numbers: the number of irreducible complex characters of degree not divisible by a prime number $p$ for a given finite group and the same number for the normalizer in that group of a Sylow $p$ -subgroup. It is named after the Canadian mathematician John McKay, who originally stated a limited version of it as a conjecture in 1971, for the special case of $p=2$ and simple groups. The conjecture was later generalized by other mathematicians to a more general conjecture for any prime value of $p$ and more general groups. In 2023, a proof of the general conjecture was announced by Britta Späth and Marc Cabanes.