{ "id": "2001.04004", "version": "v1", "published": "2020-01-12T22:08:06.000Z", "updated": "2020-01-12T22:08:06.000Z", "title": "Tilting modules arising from knot invariants", "authors": [ "Ralf Schiffler", "David Whiting" ], "comment": "18 pages, 5 Figures", "categories": [ "math.RT", "math.CO", "math.GT" ], "abstract": "We construct tilting modules over Jacobian algebras arising from knots. To a two-bridge knot $L[a_1,\\ldots,a_n]$, we associate a quiver $Q$ with potential and its Jacobian algebra $A$. We construct a family of canonical indecomposable $A$-modules $M(i)$, each supported on a different specific subquiver $Q(i)$ of $Q$. Each of the $M(i)$ is expected to parametrize the Jones polynomial of the knot. We study the direct sum $M=\\oplus_iM(i)$ of these indecomposables inside the module category of $A$ as well as in the cluster category. In this paper we consider the special case where the two-bridge knot is given by two parameters $a_1,a_2$. We show that the module $M$ is rigid and $\\tau$-rigid, and we construct a completion of $M$ to a tilting (and $\\tau$-tilting) $A$-module $T$. We show that the endomorphism algebra $\\operatorname{End}_AT$ of $T$ is isomorphic to $A$, and that the mapping $T\\mapsto A[1]$ induces a cluster automorphism of the cluster algebra $\\mathcal{A}(Q)$. This automorphism is of order two. Moreover, we give a mutation sequence that realizes the cluster automorphism. In particular, we show that the quiver $Q$ is mutation equivalent to an acyclic quiver of type $T_{p,q,r}$ (a tree with three branches). This quiver is of finite type if $(a_1,a_2)=(a_1,2), (1,a_2),$ or $(2,3)$, it is tame for $(a_1,a_2)=(2,4)$ or $(3,3)$, and wild otherwise.", "revisions": [ { "version": "v1", "updated": "2020-01-12T22:08:06.000Z" } ], "analyses": { "subjects": [ "16G20", "13F60", "57M27" ], "keywords": [ "tilting modules arising", "knot invariants", "jacobian algebra", "cluster automorphism", "two-bridge knot" ], "note": { "typesetting": "TeX", "pages": 18, "language": "en", "license": "arXiv", "status": "editable" } } }