Suppose we have an algebraic group over an algebraic closed field of prime characteristic, we may think of a subgroup of $GL_n(\bar{\mathbb{F}}_q)$ (where $\bar{\mathbb{F}}_q$ is the algebraic closure of the field with $q$ elements). 

My question is what can be said, or exists any reference for the $\mathbb{C}$-representations of that group, this is the $\mathbb{C}$-vector spaces (finite or infinite dimensional) equiped with an linear action of the group.