Figure 41

Figure 41: The Dynkin diagram of (2)+ A2. Label 1 denotes the simple root ˆα (1) of the restricted root system of 𝔲3 = 𝔰𝔲(2,1). Labels 2 and 3 correspond to the affine and overextended roots, respectively. The arrow points towards the short root which is normalized such that (ˆα1|ˆα1) = 1 2.