The differential invariants of $S{L}_2({\mathbb{F}}_3)$ acting on trace-free matrices over ${\mathbb{F}}_3$

Jonathan Elmer, Anja Meyer

Let $M$ denote the vector space of $2\times 2$ matrices with coefficients in ${\mathbb{F}}_3$ and trace zero. Let $G=S{L}_2({\mathbb{F}}_3)$. Then $G$ acts on $M$ via conjugation. Let…