 In topology he introduced and developed the bracket polynomial and Kauffman polynomial.In the mathematical field of knot theory, the bracket polynomial, also known as the "Kauffman bracket", is a polynomial invariant of framed links.Although it is not an invariant of knots or links (as it is not invariant under type I Reidemeister moves), a suitably "normalized" version yields the famous knot invariant called the Jones polynomial.