Combinatorial Methods for Detecting Surface Subgroups in Right-Angled Artin Groups

Figure 1

The group given by the graph 𝑃 on (b) injects into the group given by the graph 𝑃′ on (a). The vertex labeled by 𝑖 is referred to as 𝑣_𝑖 in the discussion below.

(a)

(b)