English

Satellite ruling polynomials, DGA representations, and the colored HOMFLY-PT polynomial

Symplectic Geometry 2019-10-10 v2 Geometric Topology

Abstract

We establish relationships between two classes of invariants of Legendrian knots in R3\mathbb{R}^3: Representation numbers of the Chekanov-Eliashberg DGA and satellite ruling polynomials. For positive permutation braids, βJ1S1\beta \subset J^1S^1, we give a precise formula in terms of representation numbers for the mm-graded ruling polynomial RS(K,β)m(z)R^m_{S(K,\beta)}(z) of the satellite of KK with β\beta specialized at z=q1/2q1/2z=q^{1/2}-q^{-1/2} with qq a prime power, and we use this formula to prove that arbitrary mm-graded satellite ruling polynomials, RS(K,L)mR^m_{S(K,L)}, are determined by the Chekanov-Eliashberg DGA of KK. Conversely, for m1m\neq 1, we introduce an nn-colored mm-graded ruling polynomial, Rn,Km(q)R^m_{n,K}(q), in strict analogy with the nn-colored HOMFLY-PT polynomial, and show that the total nn-dimensional mm-graded representation number of KK to Fqn\mathbb{F}_q^n, \mboxRepm(K,Fqn)\mbox{Rep}_m(K,\mathbb{F}_q^n), is exactly equal to Rn,Km(q)R^m_{n,K}(q). In the case of 22-graded representations, we show that Rn,K2=\mboxRep2(K,Fqn)R^2_{n,K}=\mbox{Rep}_2(K, \mathbb{F}_q^n) arises as a specialization of the nn-colored HOMFLY-PT polynomial.

Keywords

Cite

@article{arxiv.1802.10531,
  title  = {Satellite ruling polynomials, DGA representations, and the colored HOMFLY-PT polynomial},
  author = {Caitlin Leverson and Dan Rutherford},
  journal= {arXiv preprint arXiv:1802.10531},
  year   = {2019}
}

Comments

38 pages, 8 figures. Minor revisions. To appear in Quantum Topology

R2 v1 2026-06-23T00:37:01.007Z