On the Aicardi-Juyumaya bracket for tied links
O'Bryan Cárdenas-Andaur
TL;DR
The paper introduces the Aicardi-Juyumaya bracket $\langle\langle\cdot\rangle\rangle$ for tied links, addressing the lack of a Kauffman-state framework in this setting by defining AJ-states. It proves that the AJ-state contribution to $\langle\langle D\rangle\rangle$ is independent of resolution trees and provides a termination-guaranteed resolution framework via a complexity measure. An explicit algorithm to compute $\langle\langle D\rangle\rangle$ is developed, and the authors demonstrate the approach with examples that separate tied links beyond what Homflypt or the classical Kauffman bracket detect, including refinements to the tied Jones polynomial. The results open avenues for potential categorifications of tied-link invariants and strengthen the toolbox for distinguishing tied links, with computational checks that both validate and challenge prior computations.
Abstract
Given a tied link $L$, the invariant $\langle\langle\cdot\rangle\rangle$ generalizes the Kauffman bracket of classical links. However, the analogues of Kauffman states and their relationship to this invariant are not immediately clear. We address this question by defining the Aicardi-Juyumaya states, and show that the contribution of each AJ-state to $\langle\langle\cdot\rangle\rangle$ does not depend on the chosen resolution tree. We also present an algorithm to compute the double bracket of a tied link diagram, and use it to find pairs of examples of (oriented) tied links sharing the same Homflypt polynomial but different tied Jones polynomial.
