Pseudo-Riemannian Spectral Triples for $\mathrm{S}\mathrm{U}(1,1)$

We use the harmonic analysis of $\mathrm{S}\mathrm{U}(1,1)$ to show that the triple $(\mathcal{A},\mathcal{H},D)$, with $D$ (the closure of) Kostant’s cubic Dirac operator acting on the Hilbert space $\mathcal{H}=L^2(\mathrm{S}\mathrm{U}(1,1))\otimes {\mathbb{C}}^2$, and with $\ast$-algebra $\mathcal{A}=C_c^{\mathrm{\infty }}(\mathrm{S}\mathrm{U}(1,1))\otimes 1$, forms both a pseudo-Riemannian spectral triple in the sense of Van den Dungen, Paschke and Rennie, and an indefinite spectral triple in the sense of Van den Dungen and Rennie.