Time: 11AM--12NOON, 1 February 2019 Venue: Access Grid Room (Carslaw 829) Speaker: Prof. Jianquan Ge (Beijing Normal University) Title: Isoparametric polynomials and Hilbert’s 17th problem on sums of squares Abstract: We introduce a recent joint work with Prof. Zizhou Tang on nonnegative polynomials induced from isoparametric polynomials. We completely solve the question that whether they are sums of squares of polynomials, giving infinitely many explicit examples to Hilbert’s 17th problem. Lunch: There will be a seminar lunch with the detail announced after the talk.