Giulio Belletti - Finite dimensionality of the Kauffman bracket skein module
October 13, 2026
Abstract
The fact that that skein modules of closed 3-manifolds are finite dimensional is a surprising
result, first conjectured by Witten and later proven by Gunningham, Jordan, Safranov. Their proof,
which works for any skein module, relies on heavy machinery in category theory and algebraic
geometry. In this talk I will present a proof (joint with R. Detcherry) of finiteness for the Kauffman
bracket skein module ”by hand”, i.e. in an algorithmic and constructive way, that relies only on
basic properties of the KBSM. One of the advantages of this proof is that it allows, without any
modification, to also prove a version of finiteness for manifolds with boundary. As an application of
this latter result, we are able to prove that the peripheral ideal of any manifold is non-trivial, thus proving that the Reshetikhin-Turaev invariants are q-holonomic.