Orateur
Yuan Miao
Description
The spin-1/2 XXZ chain, or six-vertex model, is a prototypical quantum integrable model governed by the Yang–Baxter equation. At roots of unity, it admits non-Abelian quasi-local conserved charges generating a representation of the Onsager algebra. I will explain how this Onsager symmetry follows from the non-commuting transfer matrices of the τ2 model. The same construction yields lattice operators whose fusion rules realise the Tambara–Yamagami fusion category TY(ZN), providing a lattice counterpart of the non-invertible symmetries of the corresponding c = 1 compact boson CFT. I will conclude with implications for representation theory and quantum dynamics.