Chapter 3 Representations of 𝔰⁢𝔩2,ℂ\mathfrak{sl}_{2,\mathbb{C}}

In this section we discuss the finite-dimensional representation theory of the Lie algebra 𝔰⁢𝔩2,ℂ\mathfrak{sl}_{2,\mathbb{C}}. We then use that to study the representation theory of SL2⁡(ℂ)\operatorname{SL}_{2}(\mathbb{C}), 𝔰⁢𝔩2,ℝ\mathfrak{sl}_{2,\mathbb{R}}, SL2⁡(ℝ)\operatorname{SL}_{2}(\mathbb{R}), and SU⁢(2)\mathrm{SU}(2), which are all closely related.