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Unreduced A-polynomial distinguishing torus knots

Determine whether the unreduced A-polynomial A_K(M,L) of a knot K in S^3 distinguishes torus knots from all other knots; equivalently, establish that if A_K(M,L) equals A_{T_{a,b}}(M,L) for some torus knot T_{a,b}, then K must itself be a torus knot.

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Background

The paper proves that the enhanced A-polynomial \tilde{A}K(M,L) distinguishes torus knots (Theorem 1.2), but notes a gap for the unreduced A-polynomial A_K(M,L) due to the universal abelian factor L−1. Specifically, equality of A-polynomials could arise either from equality of enhanced A-polynomials or from an extra L−1 factor multiplying \tilde{A}{T_{a,b}}(M,L), and the latter case cannot currently be excluded.

Clarifying whether A_K(M,L) itself distinguishes torus knots would strengthen detection results and align with known relationships between A-polynomials and boundary slopes of incompressible surfaces.

References

The problem is that we cannot rule out the second case at present. We therefore pose the following: Does A_{K}(M,L) distinguish torus knots from all other knots?

Torus knots, the A-polynomial, and SL(2,C) (2405.19197 - Baldwin et al., 29 May 2024) in Question (label ‘ques:unreduced’), Section 1 (Introduction)