Published online by Cambridge University Press: 01 May 2007
In a fundamental paper in 1984, Vaughan Jones developed his new polynomialinvariant of knots using a Markov trace on the Temperley–Liebalgebra. Subsequently, Lickorish used the associated bilinear pairing toprovided an alternative proof for the existence of the 3-manifold invariants ofWitten, Reshetinkin and Turaev. A key property of this form is thenon-degeneracy of this form except at the parameter values±2cos(π/(n+1)) [7]. Koand Smolinsky derived a recursive formula for the determinants of specificminors of Markov's form, establishing the needed non-degeneracy[6]. In this paper,we define a triangular change of basis in which the form is diagonal andexplicitly compute the diagonal entries of this matrix as products of quotientsof Chebyshev polynomials, corroborating the determinant computation of Ko andSmolinsky. The method of proof employs a recursive method for defining therequired orthogonal basis elements in the Temperley–Lieb algebra,similar in spirit to Jones' and Wenzl's recursive formulafor a family of projectors in the Temperley–Lieb algebra. We define apartial order on the non-crossing chord diagram basis and give an explicitformula for a recursive construction of an orthogonal basis, via a recursionover this partial order. Finally we relate this orthogonal basis to basesconstructed using the calculus of trivalent graphs developed by Kauffman andLins [5].