English

Trace decategorification of tensor product algebras

Representation Theory 2019-03-22 v1 Quantum Algebra

Abstract

We show that in ADE type the trace of Webster's categorification of a tensor product of irreducibles for the quantum group is isomorphic to a tensor product of Weyl modules for the current algebra U˙(g[t])\dot{U}(\mathfrak{g}[t]). This extends a result of Beliakova, Habiro, Lauda, and Webster who showed that the trace of the categorified quantum group U˙(g)\dot{\mathcal{U}}^*(\mathfrak{g}) is isomorphic to U˙(g[t])\dot{U}(\mathfrak{g}[t]), and the trace of a cyclotomic quotient of U˙(g)\dot{\mathcal{U}}^*(\mathfrak{g}), which categorifies a single irreducible for the quantum group, is isomorphic to a Weyl module for U˙(g[t])\dot{U}(\mathfrak{g}[t]). We use a deformation argument based on Webster's technique of unfurling 2-representations.

Keywords

Cite

@article{arxiv.1903.08697,
  title  = {Trace decategorification of tensor product algebras},
  author = {Christopher Leonard and Michael Reeks},
  journal= {arXiv preprint arXiv:1903.08697},
  year   = {2019}
}

Comments

41 pages; preliminary version, comments welcome

R2 v1 2026-06-23T08:14:21.132Z