Gregory John Chaitin (/ˈtʃaɪtɪn/ CHY-tin; born 15 November 1947) is an Argentine-American mathematician and computer scientist. Beginning in the late 1960s, Chaitin made contributions to algorithmic information theory and metamathematics, in particular a computer-theoretic result equivalent to Gödel's incompleteness theorem. He is considered to be one of the founders of what is today known as Kolmogorov (or Kolmogorov-Chaitin) complexity together with Andrei Kolmogorov and Ray Solomonoff.